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Garmin Forerunner 255 vs Polar Street X

A

Product A: Garmin

Forerunner 255

81 of 150 known

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B

Product B: Polar

Street X

79 of 150 known

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Every value links to where we found it.

Only differences

AGarmin Forerunner 255

BPolar Street X

General

6 of 10 differ

Series

Forerunner1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Product page title is Forerunner 255, running smartwatch, 46 mm.

Street1Maker product pagepolar.com/en/street-xRead 15 October 2026Polar files it under Urban Sports Watches. The Polar guide calls the Pacer and Street watches one line.

Model numbersiMaker identifiers for this exact model and its listed variants. Excludes sibling models and other generations.

010-02641-011Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026US page for the 46 mm watch without music lists part number 010-02641-01 (Tidal Blue, $349.99). The Music toggle on the same page links the music watch to 010-02641-20, so music watches are other models. 255S is the 41 mm size, SKU 010-02641-02.

6J, 900116713, 900116714, 9001167151Maker product pagepolar.com/en/street-xRead 15 October 2026Store feed SKUs 900116713 (Night Black), 900116714 (Forest Green) and 900116715 (Snow White). The manual and the regulatory sheet give the model 6J.3Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/technical-specifications.htmRead 15 October 2026Model 6J.

GTIN / EAN

Not available

725882070766, 725882070773, 7258820707801Maker product pagepolar.com/en/street-xRead 15 October 2026Store feed gtin12: 725882070766 Night Black, 725882070773 Forest Green and 725882070780 Snow White.

AnnouncediThe maker's first announcement of this model. This is separate from first retail availability.

1 June 20223Press releasegarmin.com/en-US/newsroom/press-release/sports-fitness/garmin-celebrates-global-running-day-with-the-introduction-of-the-forerunner-255-seriesRead 11 October 2026Garmin release dated June 1, 2022.

25 March 202617Press releasepolar.com/en/media-room/polar-debuts-street-xRead 15 October 2026Press release dated 25 March 2026 from Kempele, Finland.

Status

Not available

Available1Maker product pagepolar.com/en/street-xRead 15 October 2026Global store: Buy now and in stock for three colours.

PredecessoriThe model this one directly replaced, in the same line, tier and size, as the maker or a trusted review names it.

Not available

Not available

SuccessoriThe model that directly replaced this one, in the same line, tier and size. A revision such as a Slim or OLED model does not count when a next generation exists.

Garmin Forerunner 2658Reviewdcrainmaker.com/2023/03/garmin-forerunner-review-amoled.htmlRead 11 October 2026Review: the Forerunner 265 series at first glance seems like an AMOLED version of the Forerunner 255, with several hardware differences. It follows the 255 in the Forerunner line.10Maker product pagegarmin.com/nl-NL/blogRead 23 October 2026Garmin's Dutch blog says the Forerunner 265 is the successor of the Forerunner 255.

Not available

Launch price (US)iThe maker's US launch MSRP for the stated configuration, excluding tax. Current store prices and later discounts do not qualify.

$349.993Press releasegarmin.com/en-US/newsroom/press-release/sports-fitness/garmin-celebrates-global-running-day-with-the-introduction-of-the-forerunner-255-seriesRead 11 October 2026Suggested retail price $349.99 for Forerunner 255 and 255S. Music models are $399.99.

$249.917Press releasepolar.com/en/media-room/polar-debuts-street-xRead 15 October 2026USD 249.90, excluding tax.

Launch price (EU)iThe maker's euro launch price for the stated configuration, including VAT as published. Current store prices and later discounts do not qualify.

€349.994Press articlenextpit.de/news/garmin-forerunner-255-und-955-vorgestellt-touchscreen-mehr-akkuRead 11 October 2026nextpit.de, 1 June 2022: the Forerunner 255 costs 349,99 EUR in every size, the Music edition 50 EUR more. German price incl. VAT.

€249.917Press releasepolar.com/en/media-room/polar-debuts-street-xRead 15 October 2026EUR 249.90 including VAT where applicable. GBP 219.00.

MarketsiISO country or region codes where this exact model or variant is sold. A source page's language does not establish availability.

US, DE3Press releasegarmin.com/en-US/newsroom/press-release/sports-fitness/garmin-celebrates-global-running-day-with-the-introduction-of-the-forerunner-255-seriesRead 11 October 2026US release with US dollar suggested retail prices.4Press articlenextpit.de/news/garmin-forerunner-255-und-955-vorgestellt-touchscreen-mehr-akkuRead 11 October 2026German launch pricing in euros. Documented subset together with the US release.

US, DE2Maker product pagepolar.com/us-en/street-xRead 15 October 2026The US store lists the same three colours as in stock. Its current price is 249.99 USD, which differs from the launch price of 249.90 USD and is not used.

ColoursiThe maker's own colour names

Tidal Blue1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026US store lists Tidal Blue for this model. Other regional colours exist but are not listed on this page.3Press releasegarmin.com/en-US/newsroom/press-release/sports-fitness/garmin-celebrates-global-running-day-with-the-introduction-of-the-forerunner-255-seriesRead 11 October 2026Release names tidal blue as a new colour.

Night Black, Snow White, Forest Green1Maker product pagepolar.com/en/street-xRead 15 October 2026Colour options: Night Black, Snow White, Forest Green.

Segment

Sport1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Garmin presents it as a running smartwatch.

Sport1Maker product pagepolar.com/en/street-xRead 15 October 2026Polar calls it an urban sports watch for hybrid athletes who train, work and live in the city. The store lists it in the Performance Series.

OS updates promisediYears of explicitly promised OS updates. A security-only support period does not establish an OS-upgrade promise.

Not available

Not available

Security updates untiliExact end date published for security-update support of this model. Do not calculate it from a stated number of years. A security-only period does not promise OS upgrades.

Not available

Not available

Case

5 of 8 differ

Case sizeiMarketed case-size options. The marketed size can differ from physical case height, such as ceramic editions. Base dimensions describe the smallest base-material case.

46mm1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026

45mm1Maker product pagepolar.com/en/street-xRead 15 October 2026One size. Tech specs: width 45 mm and height 45 mm.

Case shape

Round1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Specs describe the display as a diameter and the pictured case is round.

Round1Maker product pagepolar.com/en/street-xRead 15 October 2026Round case with a round AMOLED display.

Case materialiMaterial of the housing body, not just the bezel. Use Mixed when the maker describes a mixture of housing/frame materials. Read the published-material field for the parts and proportions.

Fibre-reinforced polymer6Reviewandroidcentral.com/wearables/garmin-forerunner-255-reviewRead 11 October 2026Review spec box: materials fiber-reinforced polymer. The maker lists only the bezel as fiber-reinforced polymer and no other case material.7Spec databasegadgetsandwearables.com/technical-specs/garmin-forerunner-255Read 11 October 2026Spec table: fiber-reinforced polymer bezel and case, silicone strap.

Fibre-reinforced polymer1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: case material and bezel material Bio-based plastic. The launch release says reinforced polymer body. The manual lists PA11+8GF (glass-fibre reinforced polyamide 11) among the device materials. Stored as fibre-reinforced polymer.3Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/technical-specifications.htmRead 15 October 2026Device materials list PA11+8GF, a glass-fibre reinforced polyamide.

Case material (as published)

Fiber-reinforced polymer6Reviewandroidcentral.com/wearables/garmin-forerunner-255-reviewRead 11 October 2026Review spec box wording.7Spec databasegadgetsandwearables.com/technical-specs/garmin-forerunner-255Read 11 October 2026Spec table wording.

Bio-based plastic1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: Case material Bio-based plastic.

BackiMaterial of the back of the smallest base-material case. Other materials or regional editions can differ. See source notes.

Not available

Not available

Case dimensionsiPhysical case height, width and thickness. The source note states exclusions such as the heart-rate sensor protrusion.

Height45.6Width45.6Thickness12.9mm(1.8 × 1.8 × 0.5 in)1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Specs: Physical size 45.6 x 45.6 x 12.9 mm. Not stated whether the heart rate sensor bump is included.

Height45Width45Thickness13.8mm(1.8 × 1.8 × 0.5 in)1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: width 45 mm, height 45 mm, thickness 13.8 mm.

Weight (case only)iWatch body without a strap. An unqualified published weight must not be assumed to exclude the strap.

Not available

28g(1 oz)1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: total weight without wristband 28 g.18Maker product pagepolar.com/en/guide/polar-street-x-vs-polar-pacer-proRead 15 October 2026Comparison table: 48 g, 28 g without band.

Weight with strapiWatch with the stated strap attached. Strap material and case size belong in the source note. Reviewer measurements belong in measured fields.

Not available

48g(1.7 oz)1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: total weight 48 g. This is with the POLAR Street Wristband, 22mm that comes in the box.

Durability

3 of 8 differ

Water resistanceiStatic water-pressure rating in atmospheres. It is not a safe swimming or diving depth. Diving limits are listed separately.

5ATM1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Specs: Water rating 5 ATM.

5ATM1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: water resistance WR50. The manual says 50 m, suitable for swimming.3Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/technical-specifications.htmRead 15 October 2026Water resistance 50 m (suitable for swimming).

Water resistance standard

Not available

ISO 228103Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/technical-specifications.htmRead 15 October 2026The water resistance section says Polar tests to ISO 22810 or IEC 60529. The 20, 30 and 50 m class cites ISO 22810.

Dust and water rating

Not available

Not available

Dive rating

Not available

Not available

Max dive depthiMaker-rated depth for the stated diving use, not a conversion from the water-resistance pressure rating.

Not available

Not available

MIL-STD-810iMaker claim that the watch was tested against specified MIL-STD-810 methods. It is not a guarantee for every military-standard test.

Not available

Yes1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: tested against military standard MIL-STD-810H. The tested methods are not listed.

MIL-STD-810 tests

Not available

Not available

Operating temperatureiPublished operating range. Source notes identify on-wrist limits and other operating conditions. Storage or charging limits are excluded.

Min-20Max60°C2Owner's manualwww8.garmin.com/manuals/webhelp/GUID-676967A0-1B23-4384-9BC9-76F3D643F1C8/EN-US/Forerunner_255_OM_EN-US.pdfRead 11 October 2026Specifications page 101: operating temperature -20 to 60 C. Charging range 0 to 45 C is excluded.

Min-20Max50°C1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: operation temperature -20 C to 50 C.3Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/technical-specifications.htmRead 15 October 2026Operating temperature -20 C to +50 C.

Display

7 of 14 differ

Display type

MIP1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Specs: Display type sunlight-visible, transflective memory-in-pixel (MIP).

OLED1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: display type AMOLED.

Display type (as published)

Sunlight-visible, transflective memory-in-pixel (MIP)1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026

AMOLED1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: display type AMOLED.

Screen sizeiPublished active display diagonal for a rectangular display, or diameter for a round display. Do not calculate it from pixels or display area.

1.3in(3.3 cm)1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Specs: 1.3 inch (33 mm) diameter.

1.28in(3.3 cm)1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: display size 1.28 inch.

Resolution

260 × 260px1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Specs: 260 x 260 pixels.

416 × 416px1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: display resolution 416 x 416.

Pixel densityiPublished pixel density. A rectangular diagonal formula must not be applied to a round display.

Not available

Not available

Display area

Not available

Not available

Touchscreen

No2Owner's manualwww8.garmin.com/manuals/webhelp/GUID-676967A0-1B23-4384-9BC9-76F3D643F1C8/EN-US/Forerunner_255_OM_EN-US.pdfRead 11 October 2026The manual describes control only with the LIGHT, UP, DOWN, BACK and START/STOP buttons and never mentions touch input.

Yes1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: touch screen Yes.5Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/button-functions.htmRead 15 October 2026Color touch display: swipe and tap. It is disabled during training.

Max refresh rateiHighest published display refresh rate in active operation.

Not available

Not available

Min refresh rateiLowest published display refresh rate, usually in always-on mode. It is not the active-use minimum unless stated.

Not available

Not available

Peak brightnessiMaker peak-brightness claim. It may apply to a small area or bright ambient light. Full-screen limits and battery/temperature conditions belong in source notes.

Not available

Not available

Minimum brightness

Not available

Not available

Always-on display

Not available

Yes1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: always on display Yes. The battery support page says it is off by default.14Maker product pagesupport.polar.com/en/what-is-the-battery-life-of-street-xRead 15 October 2026Always on display is off by default in Street X.

Display cover

Gorilla Glass1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026

Gorilla Glass1Maker product pagepolar.com/en/street-xRead 15 October 2026Description: 1.28 inch AMOLED touchscreen with Gorilla Glass 3.

Display cover (as published)

Corning Gorilla Glass 31Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Specs: Lens material Corning Gorilla Glass 3. Bezel material is fiber-reinforced polymer. Case material is not listed, so case_material is not stored.

Corning Gorilla Glass 3 (AF + DLC coating)1Maker product pagepolar.com/en/street-xRead 15 October 2026Manual tech spec: Corning Gorilla Glass 3 (AF + DLC coating).3Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/technical-specifications.htmRead 15 October 2026Watch materials: Corning Gorilla Glass 3 (AF + DLC coating), PA11+8GF, aluminum, stainless steel, PMMA. Wristband: silicone with an aluminum buckle.

Platform

4 of 15 differ

Platform

Proprietary1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Garmin watch software with downloadable Connect IQ watch faces, data fields and apps.

Proprietary1Maker product pagepolar.com/en/street-xRead 15 October 2026Polar own firmware. The Polar comparison guide says it runs the same OS as the Vantage V3 and Grit X2 Pro.

OS at launch

Not available

Not available

Software

Not available

Not available

Latest OS

Not available

Not available

Works with

iOS, Android1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026

iOS, Android15Maker product pagesupport.polar.com/ie-en/polar-flow-app-and-compatible-devicesRead 15 October 2026Street X works with iOS and Android phones through the Polar Flow app.

Phone requirement

Not available

iOS 17 or later, or Android 8 or later with Bluetooth 4.0 capability, running the Polar Flow app15Maker product pagesupport.polar.com/ie-en/polar-flow-app-and-compatible-devicesRead 15 October 2026Street X: iOS mobile devices with iOS 17 or later. Android mobile devices with Bluetooth 4.0 capability and Android 8 or later.

App store

Yes1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Specs list Connect IQ downloadable watch faces, data fields and apps and an on-device Connect IQ store.

Not available

Voice assistants

Not available

Not available

Chipset

Not available

Not available

Process

Not available

Not available

CPU cores

Not available

Not available

CPU configuration

AGarmin Forerunner 255

Not available

BPolar Street X

Max clock (GHz)
0.275

Source1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: CPU speed 275 MHz. Core count and type are not stated.

Max CPU clock

Not available

0.275GHz=CalculatedFrom CPU configuration

GPU

Not available

Not available

Low-power coprocessor

Not available

Not available

Memory

1 of 2 differ

RAMiKeep published GB values as stated. Convert a source explicitly labelled MB using 1000 MB per GB and preserve its original figure and unit in the note. Do not assume MB means MiB. Convert explicit MiB or GiB to decimal GB through their byte definitions, recording the conversion in the note. This normalization does not establish an exact physical byte count.

Not available

Not available

StorageiTotal built-in storage the maker states, in decimal GB. Space available to the user is lower and goes in the source note. A figure the maker gives only as available space is not stored.

4GB1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Specs: Memory/History 4 GB. The manual lists up to 4 GB of music storage for Music models only.2Owner's manualwww8.garmin.com/manuals/webhelp/GUID-676967A0-1B23-4384-9BC9-76F3D643F1C8/EN-US/Forerunner_255_OM_EN-US.pdfRead 11 October 2026Music storage up to 4 GB applies to Music models.

32 MB1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: storage 32 MB, stored as 0.032 GB. The page also lists memory 5 MB, which is not labelled RAM and is not stored.

Health sensors

3 of 8 differ

Heart rate sensor

Garmin Elevate wrist heart rate monitor1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026

Polar Precision Prime optical heart rate sensor (OHR GEN 3.5)1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: Precision Prime, OHR GEN 3.5.3Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/technical-specifications.htmRead 15 October 2026Sensors: Precision Prime, Skin Temp GEN 1, OHR GEN 3.5.

ECG capabilityiElectrical heart sensing hardware with an ECG capability. The ECG app can require an eligible country, age and paired phone.

No7Spec databasegadgetsandwearables.com/technical-specs/garmin-forerunner-255Read 11 October 2026Spec table: electrical heart rate No, ECG No. The Garmin product page lists no ECG sensor or app.

No1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: ECG none.

Blood oxygen sensingiBlood-oxygen sensing capability. App availability and medical status vary by market.

Yes1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Specs: Pulse Ox blood oxygen, spot-check and optional all-day acclimation and in sleep. Not available in all countries.

No1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: SpO2 none.

Skin temperature sensingiA sensor or supported function that measures skin temperature. It is not a core-body thermometer.

No2Owner's manualwww8.garmin.com/manuals/webhelp/GUID-676967A0-1B23-4384-9BC9-76F3D643F1C8/EN-US/Forerunner_255_OM_EN-US.pdfRead 11 October 2026The manual describes an internal temperature sensor whose reading is affected by body temperature and offers an external tempe sensor for ambient temperature. No skin temperature function is described.7Spec databasegadgetsandwearables.com/technical-specs/garmin-forerunner-255Read 11 October 2026Spec table: skin temperature No. The Garmin page lists only a thermometer.

Yes1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: Skin Temp GEN 1. Nightly skin temperature feature.

Blood pressure featureiPublished blood-pressure feature category. Hypertension notifications are not numerical blood-pressure readings.

Not available

Not available

Body composition sensor

Not available

Not available

Skin conductance (EDA)

Not available

Not available

Medical clearancesiNamed regulatory clearances and their jurisdiction. General water resistance or an ECG sensor does not establish medical clearance.

Not available

Not available

Motion and environment sensors

1 of 9 differ

Accelerometer

Yes1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026

Yes1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: accelerometer Yes.

Accelerometer range

Not available

Not available

Gyroscope

Yes1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026

Yes1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: gyroscope Yes.

Barometric altimeter

Yes1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026

Yes1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: barometer Yes.

Compass

Yes1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026

Yes1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: magnetometer compass Yes.

Ambient light sensor

No7Spec databasegadgetsandwearables.com/technical-specs/garmin-forerunner-255Read 11 October 2026Spec table: ambient light sensor No. The Garmin sensor list has none.

Yes1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: ambient light sensor Yes.

Depth gauge

Not available

Not available

Depth gauge rangeiPublished measurement range of the depth gauge, distinct from maximum diving depth and water-pressure resistance.

Not available

Not available

Water temperature sensor

Not available

Not available

Health and fitness

3 of 5 differ

Health featuresiSupported health functions with country, phone and subscription restrictions in the source notes. Upcoming functions are not counted as available.

Continuous heart rate, Heart rate alerts, Blood oxygen app, Heart rate variability, Sleep tracking, Sleep stages, Stress tracking, Cycle tracking1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Specs list heart rate every second, high and low abnormal heart rate alerts, Pulse Ox, HRV status, advanced sleep, all-day stress and women's health in Garmin Connect. Sleep stages are in the manual.2Owner's manualwww8.garmin.com/manuals/webhelp/GUID-676967A0-1B23-4384-9BC9-76F3D643F1C8/EN-US/Forerunner_255_OM_EN-US.pdfRead 11 October 2026Sleep statistics include total hours of sleep, sleep stages and sleep score (page 42 area).

Continuous heart rate, Heart rate variability, Sleep tracking, Sleep stages1Maker product pagepolar.com/en/street-xRead 15 October 2026Features: continuous heart rate, nightly sleep stages (Sleep Plus Stages), Nightly Recharge, SleepWise. HRV is listed under heart rate. The Daily Readiness card and SleepWise give an alertness forecast, not a readiness score, so readiness_score is not stored. No stress score is listed. Not a medical device.4Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/introduction.htmRead 15 October 2026Introduction: Sleep Plus Stages, Nightly Recharge, SleepWise, continuous heart rate.

Fitness featuresiSupported workout functions. A sport-profile name alone does not prove advanced metrics such as running power or running dynamics. Trackback follows the recorded route back to the start. A compass arrow that points straight to the start does not count.

VO2 max, Training load, Recovery advice, Running dynamics, Running power, Pool swim, Open water swim, Strength rep counting, Interval workouts, Route navigation, Trackback1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Specs list VO2 Max (run), training load, recovery time, running dynamics, running power, pool and open-water swim metrics, automatic rep counting, interval training, course guidance and TracBack. Running dynamics need a pod or HRM-Pro. No golf course or ClimbPro entry.2Owner's manualwww8.garmin.com/manuals/webhelp/GUID-676967A0-1B23-4384-9BC9-76F3D643F1C8/EN-US/Forerunner_255_OM_EN-US.pdfRead 11 October 2026Page 62: running power can be measured with a compatible running dynamics accessory or the watch sensors. Page 63: Running Dynamics Pod records running dynamics.

VO2 max, Training load, Recovery advice, Running power, Pool swim, Open water swim, Interval workouts, Route navigation, Turn-by-turn navigation, Trackback, Climb detection1Maker product pagepolar.com/en/street-xRead 15 October 2026Features and cards: Running Performance Test (VO2max), Training Load Pro, Recovery Pro, wrist-based running power, swimming metrics, interval timers and phased training targets, route guidance, turn-by-turn route guidance, Track Back, Back to Start. Hill Splitter detects uphills and downhills automatically (manual). The manual has separate pool and open water swimming sections.4Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/introduction.htmRead 15 October 2026Introduction: Route Guidance, Komoot routes, Track back, Back to start, Running Performance Test with VO2max, Walking test, Training Load Pro, Recovery Pro, running power, swimming metrics with distance and strokes also in open water, Hill Splitter.9Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/swimming-metrics.htmRead 15 October 2026Separate sections for pool swimming (distance, pace, strokes, SWOLF) and open water swimming (distance, pace, stroke rate for freestyle and route).10Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/hill-splitter.htmRead 15 October 2026Hill Splitter automatically detects all uphills and downhills from GPS speed, distance and barometric altitude. It needs a 1 second GPS recording rate. Stored as climb detection.13Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/track-back-and-back-to-start.htmRead 15 October 2026Track back guides you back to the start via the same route you came. Back to start shows the direction by beeline.

Sport profilesiPublished count of distinct sport/activity profiles. A claim such as 180+ is not an exact integer count.

Not available

Not available

Dive modesiActual supported dive modes. Water resistance or a depth app alone does not establish decompression-capable scuba support.

Not available

Not available

External sensorsiTypes of external workout sensors the watch can pair with. GPS reception, phone data and built-in sensors do not qualify.

Heart rate strap, Power meter, Speed and cadence, Foot pod, Smart trainer1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Specs list heart rate from external HRM, power meter compatible, speed and cadence sensor support, foot pod capable and smart trainer control.

Heart rate strap, Power meter, Speed and cadence8Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/compatible-sensors.htmRead 15 October 2026Compatible Bluetooth sensors: Polar Verity Sense, OH1, H10 and H9 heart rate sensors, Polar speed sensor and cadence sensor, and third-party power sensors.

Safety

4 of 6 differ

Fall detectioniAutomatic fall detection. Incident detection restricted to recorded workouts is not counted as general fall detection.

No1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Specs list only incident detection during select activities, which is limited to certain outdoor activities. Not counted as general fall detection.2Owner's manualwww8.garmin.com/manuals/webhelp/GUID-676967A0-1B23-4384-9BC9-76F3D643F1C8/EN-US/Forerunner_255_OM_EN-US.pdfRead 11 October 2026Page 83: incident detection is a supplemental feature available only for certain outdoor activities.

Not available

Car crash detection

Not available

Not available

Emergency SOSiA manual emergency alert to emergency services or preset contacts. Source notes identify the recipient, paired-phone requirement and country limits. Satellite is listed separately.

Yes1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Specs list Assistance. The manual says it sends a message with name, LiveTrack link and GPS location to emergency contacts through a paired phone with data. It does not call emergency services.2Owner's manualwww8.garmin.com/manuals/webhelp/GUID-676967A0-1B23-4384-9BC9-76F3D643F1C8/EN-US/Forerunner_255_OM_EN-US.pdfRead 11 October 2026Safety and Tracking, page 84: Assistance sends a message with name, LiveTrack link and GPS location to emergency contacts. Paired phone with data plan required.

Not available

Emergency sireniPublished or measured siren sound level in decibels. Audible distance alone does not establish this value. Measurement distance belongs in source notes.

Not available

Not available

Live location sharingiShares live location during supported use. A paired phone or data subscription may be required.

Yes1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Specs list live event sharing (Android only). The manual lists LiveTrack.2Owner's manualwww8.garmin.com/manuals/webhelp/GUID-676967A0-1B23-4384-9BC9-76F3D643F1C8/EN-US/Forerunner_255_OM_EN-US.pdfRead 11 October 2026Safety and Tracking: LiveTrack lets friends and family follow activities in real time.

Not available

Dedicated LED flashlightiA dedicated hardware LED flashlight. Lighting the display white is not counted.

No2Owner's manualwww8.garmin.com/manuals/webhelp/GUID-676967A0-1B23-4384-9BC9-76F3D643F1C8/EN-US/Forerunner_255_OM_EN-US.pdfRead 11 October 2026Controls menu: Flashlight turns on the screen to use the watch as a flashlight. A lit display is not a dedicated LED.7Spec databasegadgetsandwearables.com/technical-specs/garmin-forerunner-255Read 11 October 2026Spec table: LED flashlight No, matching the manual.

Yes1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: front LED light Yes. Built-in LED flashlight with red light mode.11Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/flashlight.htmRead 15 October 2026Integrated LED flashlight with adjustable white light and a red light mode.

Positioning

2 of 3 differ

PositioningiPublished satellite systems and signal bands. Do not infer bands from dual-frequency support alone.

GPS, GLONASS, Galileo, QZSS, BeiDou1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Specs list GPS, GLONASS, Galileo, QZSS and BeiDou. Multi-band GPS is listed. Signal bands are not named.

GPS, Galileo, BeiDou, QZSS1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs, Geo location: GPS, Galileo, BeiDou and QZSS Yes. GLONASS is not listed.18Maker product pagepolar.com/en/guide/polar-street-x-vs-polar-pacer-proRead 15 October 2026Comparison table: GPS constellations GPS, Galileo, BeiDou, QZSS for Street X. GLONASS is not named.

Dual-band GNSSiMaker-stated dual-frequency satellite reception. Supported constellations and signal bands are listed separately.

Yes1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Specs list Multi-band GPS. Battery table calls it All-Systems GNSS plus Multi-Band.

Not available

Offline mapsiMap data stored on the watch and usable without live phone data. GPX routes or breadcrumb tracks alone are not offline maps.

No1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026No map entry in the specs. Only breadcrumb trail, courses and TracBack are listed, which are not offline maps.

No19Spec databasethe5krunner.com/specs/polar/street-xRead 15 October 2026No onboard maps. Route guidance uses planned routes and breadcrumbs.

Connectivity

6 of 15 differ

BluetoothiPublished Bluetooth support for this model. The version is recorded separately. Unknown version does not mean the radio is absent.

Yes1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026

Yes1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: Bluetooth technology Bluetooth LE.

Bluetooth version

Not available

Not available

Wi-FiiPublished Wi-Fi support for this model. The standard and bands are recorded separately. Unknown standard does not mean Wi-Fi is absent.

No2Owner's manualwww8.garmin.com/manuals/webhelp/GUID-676967A0-1B23-4384-9BC9-76F3D643F1C8/EN-US/Forerunner_255_OM_EN-US.pdfRead 11 October 2026Status icons: Wi-Fi technology status for Forerunner music watches only. The spec table lists no Wi-Fi for this model.

No1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs, Connectivity lists Bluetooth LE and the USB cable only.

Wi-Fi standard

Not available

Not available

Wi-Fi bands

Not available

Not available

CellulariTrue when a cellular edition is sold. A variant row states whether that individual model has cellular hardware.

No1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Specs list Connectivity as Bluetooth and ANT+ only. No Wi-Fi and no cellular.

No1Maker product pagepolar.com/en/street-xRead 15 October 2026Connectivity lists Bluetooth LE and the USB cable only. No cellular radio is listed.

Network

Not available

Not available

4G bandsiPublished LTE bands for the stated regional cellular model. Do not transfer bands to another region or Wi-Fi-only model.

Not available

Not available

5G bandsiPublished 5G NR bands for the stated regional cellular model. RedCap support does not establish conventional full-bandwidth phone 5G.

Not available

Not available

NFCiSome regions sell an NFC edition, so it is per variant.

Yes1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Garmin Pay contactless payments are listed. NFC itself is not named in the specs.

No19Spec databasethe5krunner.com/specs/polar/street-xRead 15 October 2026NFC not listed. The page says the watch has no contactless payment.

Contactless payments

Yes1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Garmin Pay is listed.

No19Spec databasethe5krunner.com/specs/polar/street-xRead 15 October 2026No contactless payment.

Payment services

Garmin Pay1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026

Not available

Ultra-wideband

No7Spec databasegadgetsandwearables.com/technical-specs/garmin-forerunner-255Read 11 October 2026Spec table: UWB No. Garmin lists Bluetooth and ANT+ only.

Not available

Satellite

Not available

None1Maker product pagepolar.com/en/street-xRead 15 October 2026Connectivity lists Bluetooth LE and the USB cable only. No satellite link is listed.

ANT+

Yes1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026

No19Spec databasethe5krunner.com/specs/polar/street-xRead 15 October 2026ANT+ not listed. Connectivity is Bluetooth LE.

Audio

3 of 4 differ

Speaker

No7Spec databasegadgetsandwearables.com/technical-specs/garmin-forerunner-255Read 11 October 2026Spec table: speakers No. Garmin lists no voice calls, speaker or music playback for this non-music model.

Not available

Microphones

07Spec databasegadgetsandwearables.com/technical-specs/garmin-forerunner-255Read 11 October 2026Spec table: microphone No. Garmin lists no voice calls or microphone for this model.

Not available

Calls on the watchiVoice-call capability of the marketed model, including sold cellular editions. Variant radio capability and paired-phone requirements still apply.

None1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Specs list text response and reject phone call with text only. No voice call, speaker or microphone entry and no cellular. No voice calls on the watch.

Not available

Music on the watchiPlays audio stored on the watch. Remote control of phone playback or streaming alone does not qualify.

No2Owner's manualwww8.garmin.com/manuals/webhelp/GUID-676967A0-1B23-4384-9BC9-76F3D643F1C8/EN-US/Forerunner_255_OM_EN-US.pdfRead 11 October 2026Specifications page 101 lists music media storage for Forerunner music watches (Forerunner 255 Music). This model is the non-music watch.

No19Spec databasethe5krunner.com/specs/polar/street-xRead 15 October 2026No music storage.

Controls

3 of 5 differ

ButtonsiPhysical controls used to operate the watch, excluding the rotating crown and strap-release buttons. A clickable rotating crown is counted only in Crown.

52Owner's manualwww8.garmin.com/manuals/webhelp/GUID-676967A0-1B23-4384-9BC9-76F3D643F1C8/EN-US/Forerunner_255_OM_EN-US.pdfRead 11 October 2026Overview, page 2: LIGHT, UP, DOWN, BACK and START/STOP.

55Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/button-functions.htmRead 15 October 2026Your watch has five buttons: CUSTOM (LIGHT), BACK, OK, UP and DOWN. The touch display adds touch control.

Named operating buttonsiNames of operating buttons, excluding the crown and strap-release controls.

LIGHT, UP, DOWN, BACK, START/STOP2Owner's manualwww8.garmin.com/manuals/webhelp/GUID-676967A0-1B23-4384-9BC9-76F3D643F1C8/EN-US/Forerunner_255_OM_EN-US.pdfRead 11 October 2026Overview page 2. START and STOP share one button.

LIGHT (custom button), BACK, OK, UP, DOWN5Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/button-functions.htmRead 15 October 2026Button functions: CUSTOM BUTTON (turns the flashlight on or off by default), BACK, OK, UP/DOWN.

CrowniA crown that rotates to control the interface. A round push button that does not rotate is not a crown.

None2Owner's manualwww8.garmin.com/manuals/webhelp/GUID-676967A0-1B23-4384-9BC9-76F3D643F1C8/EN-US/Forerunner_255_OM_EN-US.pdfRead 11 October 2026Overview shows five buttons and no crown.

None5Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/button-functions.htmRead 15 October 2026No crown is described. Controls are five buttons and the touch display.

Rotating bezeliPhysical rotation or touch gestures around the display edge. A fixed decorative bezel is None.

None2Owner's manualwww8.garmin.com/manuals/webhelp/GUID-676967A0-1B23-4384-9BC9-76F3D643F1C8/EN-US/Forerunner_255_OM_EN-US.pdfRead 11 October 2026Overview shows five buttons and no rotating bezel.

Not available

Gestures

Raise and turn your arm to turn on the backlight2Owner's manualwww8.garmin.com/manuals/webhelp/GUID-676967A0-1B23-4384-9BC9-76F3D643F1C8/EN-US/Forerunner_255_OM_EN-US.pdfRead 11 October 2026Backlight settings: Gesture turns on the backlight by raising and turning your arm to look at your wrist.

Not available

Battery and charging

8 of 13 differ

Battery capacityiPublished battery capacity for the stated case size. Rated and typical capacity are distinguished in source notes.

Not available

385mAh1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: battery capacity 385 mAh, Li-Pol.3Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/technical-specifications.htmRead 15 October 2026385 mAh Li-pol rechargeable battery, replaceable at Polar Central Service.

Claimed battery lifeiMaker endurance claims with distinct operating modes and case sizes. With solar describes augmentation of that estimate, not hardware capability. Use false for ordinary claims without solar augmentation, true for explicitly solar-aided claims, and omit it when solar qualification is unclear. Source notes state AOD, GNSS, music and solar conditions. Do not create a normal-use row from an AOD-only claim. Low power denotes the maker battery-saver mode. Keep its typical, light-use and always-on claims separate from standard-mode claims. GPS power saving identifies an intermediate reduced-accuracy GNSS saving preset. Source notes retain the maker's preset name and published conditions. Max battery GPS is the distinct maximum-saving claim. When the maker has only one GPS saving preset, it is GPS power saving.

AGarmin Forerunner 255

Mode	With solar	Hours (h)
Smartwatch	No	336
GPS	No	30
GPS, all systems	No	25
GPS, dual-band	No	16

Source1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Smartwatch mode up to 14 days (336 h). GPS-only GNSS up to 30 h. All-Systems GNSS up to 25 h. All-Systems plus Multi-Band up to 16 h. Manual footnote: smartwatch mode includes activity tracking, phone notifications and wrist heart rate.

BPolar Street X

Mode	With solar	Hours (h)
Smartwatch	No	240
GPS	No	42
Max battery GPS	No	170

Source1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: performance training mode 42 h, eco training mode 170 h, smartwatch mode 10 d. The page text and the launch release say 43 h for the performance mode, which conflicts with the 42 h in the tech specs and the manual. The manual figure is stored.3Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/technical-specifications.htmRead 15 October 2026Performance training mode up to 42 h (optical heart rate on, GPS recording every second). Eco training mode up to 170 h (GPS every 2 minutes, optical heart rate off). Smartwatch mode up to 10 days with continuous heart rate and phone notifications on. 10 days is 240 h.14Maker product pagesupport.polar.com/en/what-is-the-battery-life-of-street-xRead 15 October 2026Performance up to 42 h: optical heart rate on, GPS every 1 second, always-on display off. The scenario text says Dual-Frequency GPS ON, while the product page never claims dual-frequency GNSS and the5krunner says single-frequency, so the row is stored as plain GPS. Eco up to 170 h: optical heart rate off, single-frequency GPS every 2 minutes. Smartwatch up to 10 days with phone notifications on, always-on display off and Do Not Disturb 8 h at night. Stored eco row as the maximum-saving GPS mode, like the Vantage V3 file.

Smartwatch mode (claimed)iMaker normal-use smartwatch claim without solar. A watch with only an explicit AOD-mode claim has no value here. Workloads differ and source notes must be read.

336h=CalculatedFrom Claimed battery life

240h=CalculatedFrom Claimed battery life

AOD battery life (up to)iMaker claimed smartwatch endurance with the always-on display enabled and without solar, for the base case. Source notes preserve workload and case conditions. This is a claim, not a measured test or an AOD-off estimate.

Not available

Not available

GPS mode (claimed)iMaker regular GPS/GNSS activity claim without solar, for the base case. AOD, multi-band, music and power-saving conditions have separate rows when published.

30h=CalculatedFrom Claimed battery life

42h=CalculatedFrom Claimed battery life

Solar chargingiPublished solar charging hardware capability. An ordinary battery estimate without solar augmentation does not prove that the watch lacks solar charging hardware.

No9Reviewdcrainmaker.com/2022/06/garmin-forerunner-multisport.htmlRead 11 October 2026Review covers the Forerunner 255, 255S, 255 Music and 255S Music with no solar model. Solar is introduced in this launch only on the Forerunner 955 Solar.

Not available

Charging methodiThe connection at the watch, not the cable end at the USB adapter. A proprietary inductive puck is not Qi unless interoperability is explicitly established.

Proprietary plug1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Specs: Garmin proprietary plug charger.

Magnetic pins1Maker product pagepolar.com/en/street-xRead 15 October 2026Tech specs: USB cable Proprietary / USB-C. The cable snaps on magnetically (manual).

Charging guidanceiPublished charging requirements, nominal estimates and compatibility guidance. Keep adapter ratings separate from power accepted by the watch.

Not available

Charge with the included Polar Charge 2.0 cable, which snaps on magnetically. A USB power adapter is not included. Polar asks for an adapter marked output 5 Vdc that provides at least 500 mA and has an approval mark such as LPS, UL listed or CE. The watch can charge during training. An optional charge limit of 80% is in the battery settings.6Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/batteries.htmRead 15 October 2026Charging the battery: custom cable snaps in magnetically. A USB power adapter is not included. Adapter marked output 5 Vdc, at least 500 mA, LPS, UL listed or CE. Charging during training is possible. Charge limit 80% in Settings > General settings > Battery.

Max charging power (watch)iPublished maximum charging power at the watch. Adapter rating or charger input power does not prove the power accepted by the watch.

Not available

Not available

Fast chargingiAn explicit fast-charging capability claim. A short charging time or high adapter wattage alone does not qualify.

Not available

Not available

Quick charge claimiMaker claim for usage from a short charge. Source notes identify the usage workload, such as normal use or sleep tracking.

Not available

Not available

Charge 0 to 80% (claimed)iMaker claim for charging an empty battery to 80%. Charger and approximate qualifiers belong in source notes.

Not available

Not available

Full charge time (claimed)iMaker advertised nominal full-charge duration. Approximate or theoretical maker estimates are allowed, with their conditions in source notes. Partial-charge intervals do not qualify. Measured 0 to 100% tests have a separate field.

120min2Owner's manualwww8.garmin.com/manuals/webhelp/GUID-676967A0-1B23-4384-9BC9-76F3D643F1C8/EN-US/Forerunner_255_OM_EN-US.pdfRead 11 October 2026Tips for charging: charging a fully depleted battery takes up to two hours, from a Garmin approved AC adapter or a computer USB port. Stored as a nominal claim of 120 minutes with the up-to qualifier.

Not available

Measured

None of 4 known

Peak brightness (measured)iReviewer measurement. Source notes state screen area, mode and ambient light. A small-area peak claim cannot be replaced with a full-screen measurement.

Not available

Not available

Battery life (measured)iReviewer-observed mixed-use endurance. Source notes state case size, AOD, workout use and whether it was a complete discharge. Extrapolation from partial discharge is excluded.

Not available

Not available

Battery tests (measured)iReviewer-observed endurance, with case size and test settings in source notes. Partial-discharge projections are not stored as measured endurance.

Not available

Not available

Full charge time (measured)iReviewer measurement from empty to full, not 0-80% or a charge from 5%. Source notes name the charger and case size.

Not available

Not available

Strap

3 of 6 differ

Lug widthiDistance between standard strap attachment lugs, not the decorative width of a proprietary strap. Unknown for custom connectors unless the maker publishes lug width.

22mm1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Specs: quick release bands, 22 mm, industry standard.

22mm7Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/changeable-wristband.htmRead 15 October 2026Compatible with standard 22 mm wristbands, no adapters needed.

Quick-release strapiThe supplied strap can be detached through its quick-release mechanism. Compatibility with quick-release replacement straps alone does not qualify.

Yes1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026

Yes7Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/changeable-wristband.htmRead 15 October 2026To detach a band, pull the quick-release knob inwards.

Strap systemiPublished attachment system and compatible case sizes. Proprietary connectors are distinguished from standard spring bars.

Industry standard 22 mm quick release bands1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026

Standard 22 mm spring bars with a quick-release knob. No adapters needed7Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/changeable-wristband.htmRead 15 October 2026Standard 22 mm spring bars. Any band that uses 22 mm spring bars fits.

Strap materialiMaterial of the supplied strap for the stated package. Do not substitute material from another band sold separately.

Silicone1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Specs: Strap material silicone.

Silicone3Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/technical-specifications.htmRead 15 October 2026Wristband: silicone, aluminum buckle, stainless steel spring bars.

Strap

Not available

POLAR Street Wristband, 22mm1Maker product pagepolar.com/en/street-xRead 15 October 2026What's included: POLAR Street Wristband, 22mm.

Strap sizesiPublished wrist-circumference range for the stated strap or case. Source notes distinguish an overall compatible wrist range from one supplied strap size.

AGarmin Forerunner 255

Wrist (min) (mm)	Wrist (max) (mm)
130	205

Source1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Specs: fits wrists with a circumference of 130-205 mm. This is the overall range for the watch with its supplied silicone strap.

BPolar Street X

Not available

Regulatory

1 of 3 differ

FCC ID

Not available

INW6J16Regulatory filingsupport.polar.com/e_manuals/Regulatory_information/enote-rf-street-x.pdfRead 15 October 2026Model number 6J, FCC ID INW6J, IC 6248A-6J.

SAR limb (US)iPublished limb/wrist SAR for the stated base regional model under the US regime. Other case sizes or radio versions can differ. Head or body SAR is excluded.

Not available

Not available

SAR limb (EU)iPublished limb/wrist SAR for the stated base regional model under the EU regime. Other case sizes or radio versions can differ. Head or body SAR is excluded.

Not available

Not available

Other certifications

ANT+ certified2Owner's manualwww8.garmin.com/manuals/webhelp/GUID-676967A0-1B23-4384-9BC9-76F3D643F1C8/EN-US/Forerunner_255_OM_EN-US.pdfRead 11 October 2026Front matter: this product is ANT+ certified.

Not available

In the box

1 of 2 differ

In the box

Forerunner 255, Charge/data cable, Documentation1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026In the Box tab: Forerunner 255, charge/data cable, documentation.

POLAR Street X, POLAR Street Wristband, 22mm, Polar Charge 2.01Maker product pagepolar.com/en/street-xRead 15 October 2026What's included: POLAR Street X, POLAR Street Wristband 22 mm, Polar Charge 2.0.

Power adapter in boxiA mains/USB power adapter is supplied. A charging cable, inductive puck or charging dock alone does not count.

No1Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026Box lists a charge/data cable and no power adapter.

No1Maker product pagepolar.com/en/street-xRead 15 October 2026The box has the watch, the wristband and the Polar Charge 2.0 cable. No power adapter is listed.

Links

Not compared

Product page

www.garmin.com/en-US/p/780139/pn/010-02641-011Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026US store page for SKU 010-02641-01.

www.polar.com/en/street-x1Maker product pagepolar.com/en/street-xRead 15 October 2026The maker's product page.

Spec sheet

www.garmin.com/en-US/p/780139/pn/010-02641-011Maker product pagegarmin.com/en-US/p/780139/pn/010-02641-01Read 11 October 2026The specs tab of the US product page holds the full specification list for the 46 mm watch.

support.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/technical-specifications.htm3Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/technical-specifications.htmRead 15 October 2026Street X user manual technical specification page.

Manual

www8.garmin.com/manuals/webhelp/GUID-676967A0-1B23-4384-9BC9-76F3D643F1C8/EN-US/Forerunner_255_OM_EN-US.pdf2Owner's manualwww8.garmin.com/manuals/webhelp/GUID-676967A0-1B23-4384-9BC9-76F3D643F1C8/EN-US/Forerunner_255_OM_EN-US.pdfRead 11 October 2026

support.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/introduction.htm4Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/introduction.htmRead 15 October 2026Polar Street X user manual, introduction.

EPREL registration numberiId in the EU energy label database. Each size or model of a series has its own id, so it is per variant.

Not available

Not available

Warranty

1 of 1 differ

Manufacturer warranty (source market)iThe maker's warranty period for the exact SKU or configuration and market named in the source note. It applies only to that stated market, not every regional variant. Statutory consumer rights are excluded. The base term is stored. An extension that needs registration goes in the source note.

1year5Maker product pagegarmin.com/en-US/legal/consumer-limited-warrantyRead 11 October 2026Garmin consumer limited warranty, US: non-aviation products are free from defects in materials or workmanship for one year from the date of purchase.

2years12Owner's manualsupport.polar.com/e_manuals/street-x/polar-street-x-user-manual-english/guarantee.htmRead 15 October 2026Limited International Polar Guarantee: two years from the date of purchase. Silicone or plastic wristbands one year.

Both are also in the API. Back to all smartwatches.