WatchFitTool

Garmin Fenix 8 43mm AMOLED vs Forerunner 265S

Size, specs & wrist fit compared

Garmin fēnix® 8 – 43 mm, AMOLED010-02903-10
Garmin fēnix® 8 – 43 mm, AMOLED
Garmin Forerunner® 265S010-02810-04
Garmin Forerunner® 265S
41.7mm × 41.7mmCheck offerView specs

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Which one fits you

Both need much the same wrist — roughly 44–61mm across the flat of the wrist. Neither will fit where the other won't, so decide on thickness, weight and features instead.

The Fenix 8 43mm AMOLED wears larger than the Forerunner 265S (43mm vs 41.7mm case), giving it more wrist presence — and needing a wider wrist to sit cleanly.

The Forerunner 265S is the slimmer of the two (12.9mm vs 13.8mm), so it slides under a cuff more easily.

On the wrist the Forerunner 265S feels lighter (39g vs 66g, case only).

Among the 318 43mm watches we hold thickness for, the Fenix 8 43mm AMOLED is thicker than 70% — it will sit high even though the case width reads modest.

The Forerunner 265S is middle-of-the-pack for thickness among the 642 42mm watches in the database.

The Fenix 8 43mm AMOLED is 1.3mm wider, 1.3mm longer, 0.9mm thicker and 27g heavier than the Forerunner 265S. Both are circular.

fēnix® 8 – 43 mm, AMOLED

Forerunner® 265S

Case width
43mm
41.7mm−1.3mm
Lug-to-lug
43mm
41.7mm−1.3mm
Thickness
13.8mm
12.9mm−0.9mm
Weight
66g
39g−27g

Switch or add watches

Garmin fēnix® 8 – 43 mm, AMOLED

Garmin

fēnix® 8 – 43 mm, AMOLED

Garmin Forerunner® 265S

Garmin

Forerunner® 265S

Fit tool

Watch Fit Tool

For sports watches, lug-to-lug (L2L) is what matters most — it decides whether a watch overhangs your wrist. Bulky is fine; overhang is not.

Your wrist
mm
≈ 146.9mm around

Garmin fēnix® 8 – 43 mm, AMOLED

Case 43.0mm · Lug-to-lug 43.0mm · Thickness 13.8mm · 66g

Balanced Fit

43mm on a 55mm wrist

10:09TUE 12lug to lug 43.0mmyour wrist 55.0mm

Across the wrist it works — 6.0mm spare each side — but a tall watch on this wrist. Fine over a sleeve, awkward under one.

On a 55mm wrist the sweet spot is 47–53mm lug to lug. This one is 43mm, so you could go bigger.

How to Measure

Measure where you wear it, just below the wrist bone. Either of these works — the tool converts between them.

  1. 1. Flat width — arm flat on a table, palm up. Measure straight across the top of the wrist, bone to bone, ignoring the curve down the sides.
  2. 2. Around — a tape, or a strip of paper marked and held against a ruler, snug the whole way round.
Complete Wrist Measurement Guide →
Against one you know

Leather: Attaches at the lugs, so the case back rests on your skin. Thins and softens with wear. Typical figures, not this model’s own.

Show the measurements
  • Across the wrist6.0mm spare each side

    Comfortable, with visible skin either side.

  • Off the wrist13.8mm off the skin

    A tall watch on this wrist. Fine over a sleeve, awkward under one. (13.8mm case, back against the skin)

  • How it seats~4.4mm under the rim

    Seats well, with the case back following most of the wrist.

  • Weight on the wrist66g

    Substantial without being a burden — the usual weight of a steel watch on a wrist this size. (1.2g per mm of wrist)

Garmin Forerunner® 265S

Case 41.7mm · Lug-to-lug 41.7mm · Thickness 12.9mm · 39g

Balanced Fit

41.7mm on a 55mm wrist

10:09TUE 12lug to lug 41.7mmyour wrist 55.0mm

Comfortably inside the edges of your wrist, and it seats and sits low enough to wear without thinking about it.

On a 55mm wrist the sweet spot is 47–53mm lug to lug. This one is 41.7mm, so you could go bigger.

How to Measure

Measure where you wear it, just below the wrist bone. Either of these works — the tool converts between them.

  1. 1. Flat width — arm flat on a table, palm up. Measure straight across the top of the wrist, bone to bone, ignoring the curve down the sides.
  2. 2. Around — a tape, or a strip of paper marked and held against a ruler, snug the whole way round.
Complete Wrist Measurement Guide →
Against one you know

Leather: Attaches at the lugs, so the case back rests on your skin. Thins and softens with wear. Typical figures, not this model’s own.

Show the measurements
  • Across the wrist6.6mm spare each side

    Comfortable, with visible skin either side.

  • Off the wrist12.9mm off the skin

    Normal sports-watch height for a wrist this size. (12.9mm case, back against the skin)

  • How it seats~3.9mm under the rim

    Seats well, with the case back following most of the wrist.

  • Weight on the wrist39g

    Light enough to forget you have it on. (0.7g per mm of wrist)

2D Dimension Schematics

Every case drawn to scale on a shared centre — from above, and in profile against the wrist.

Highlight
From above — same centre, true scale
From the side — how far each sits off the wrist
  • Garmin fēnix® 8 – 43 mm, AMOLED43mm · 13.8mm thick
  • Garmin Forerunner® 265S41.7mm · 12.9mm thick

3D preview

fēnix® 8 – 43 mm, AMOLED vs Forerunner® 265S on a wrist

Sized to your own wrist, turned any way you like.

Open 3D try-on

Shapes are built from published measurements, not manufacturer 3D models — accurate proportions, generic dial.

Battery life compared

Furthest apart in Smartwatch mode, where the Forerunner 265S lasts 1.5× as long as the Fenix 8 43mm AMOLED (15 days against 10 days).

Fenix 8 43mm AMOLEDForerunner 265S

  • Battery Saver

    15 days
    —
  • Smartwatch

    10 days
    15 days
  • Expedition GPS

    10 days
    —
  • Max Battery GPS

    49 hours
    —
  • GPS Only

    28 hours
    —
  • GPS-Only GNSS

    —
    24 hours
  • All Satellite Systems

    23 hours
    —
  • All Satellite Systems + Multi-band

    21 hours
    —
  • SatIQ GNSS

    —
    18 hours
  • All-Systems GNSS + Multi-Band

    —
    15 hours
  • GPS-Only GNSS with music

    —
    7.5 hours
  • SatIQ GNSS with music

    —
    7 hours
  • All Satellite Systems + Music

    6 hours
    —
  • All-Systems GNSS + Multi-Band with music

    —
    6 hours

Specifications

The short version

7 key specs
SpecGarminfēnix® 8 – 43 mm, AMOLEDGarminForerunner® 265S
Case Width43mm41.7mm
Thickness13.8mm12.9mm
Weight66g39g
ShapeCircularCircular
Display typeAMOLEDAMOLED (optional always-on mode)
Battery lifeSmartwatch: Up to 10 days (4 days always-on) Battery Saver Watch Mode: Up to 15 days GPS Only: Up to 28 hours (22 hours always-on) All Satellite Systems: Up to 23 hours (18 hours always-on) All Satellite Systems + Multi-band: Up to 21 hours (16 hours always-on)* All Satellite Systems + Music: Up to 6 hours Max Battery GPS: Up to 49 hours Expedition GPS: Up to 10 days *Assuming typical use with SatIQ technologySmartwatch mode: Up to 15 days GPS-Only GNSS mode: Up to 24 hours SatIQ (AutoSelect) GNSS mode: Up to 18 hours All-Systems GNSS mode + Multi-Band: Up to 15 hours GPS-Only GNSS mode with music: Up to 7.5 hours SatIQ (AutoSelect) GNSS mode with music: Up to 7 hours All-Systems GNSS mode + Multi-Band with music: Up to 6 hours See Details
Released20242023

Every specification

338 specs
SpecGarmin fēnix® 8 – 43 mm, AMOLEDGarmin Forerunner® 265S
Overview
FamilyGarminGarmin
General
Battery lifeSmartwatch: Up to 10 days (4 days always-on) Battery Saver Watch Mode: Up to 15 days GPS Only: Up to 28 hours (22 hours always-on) All Satellite Systems: Up to 23 hours (18 hours always-on) All Satellite Systems + Multi-band: Up to 21 hours (16 hours always-on)* All Satellite Systems + Music: Up to 6 hours Max Battery GPS: Up to 49 hours Expedition GPS: Up to 10 days *Assuming typical use with SatIQ technologySmartwatch mode: Up to 15 days GPS-Only GNSS mode: Up to 24 hours SatIQ (AutoSelect) GNSS mode: Up to 18 hours All-Systems GNSS mode + Multi-Band: Up to 15 hours GPS-Only GNSS mode with music: Up to 7.5 hours SatIQ (AutoSelect) GNSS mode with music: Up to 7 hours All-Systems GNSS mode + Multi-Band with music: Up to 6 hours See Details
Battery typeLithium ionLithium ion
Display Size1.3” (33.00 mm) diameter1.1" (28.1 mm) diameter
Case materialfiber-reinforced polymer with metal rear cover—
Color displayYesYes
Lens MaterialCorning® Gorilla® Glass or sapphire crystalCorning® Gorilla® Glass 3
Bezel Materialstainless steel or titaniumfiber-reinforced polymer
Memory/History32 GB8 GB
Strap materialsiliconesilicone
Charging methodGarmin proprietary plug chargerGarmin proprietary plug charger
Large font optionYesYes
Display resolution416 x 416 pixels360 x 360 pixels
Built-in speaker/microphoneYes—
Leakproof inductive buttonsYes—
QuickFit® watch band compatibleincluded (20 mm)—
Quick Release bands—yes (18 mm, Industry standard)
Sensors
GPSYesYes
QZSSYesYes
BeiDouYesYes
CompassYesYes
GLONASSYesYes
GalileoYesYes
GyroscopeYesYes
ThermometerYesYes
Depth sensoryes (to 40 m)—
AccelerometerYesYes
SatIQ™ TechnologyYesYes
Ambient light sensorYesYes
Barometric altimeterYesYes
Pulse Ox Blood Oxygen Saturation MonitorYesYes
Garmin Elevate™ wrist heart rate monitorYesYes
Product Info
Main SKU010-02903-10010-02810-04
Product ID1228493886689
Product Namefēnix® 8 – 43 mm, AMOLEDForerunner® 265S
Release Date8/27/20243/2/2023
Product VariationSapphire, Soft Gold with Fog Gray/Dark Sandstone Silicone BandBlack Bezel with Whitestone Case and Whitestone/Neo Tropic Silicone Band
Clock Features
TimerYesYes
StopwatchYesYes
Time/dateYesYes
Alarm clockYesYes
GPS Time SyncYesYes
Sunrise/sunset timesYesYes
Automatic daylight saving timeYesYes
Diving Features
PO2up to 1.6 with customizable Deco settings—
TidesYes—
Backlightyes (configurable intensity; always on)—
Gas mixesAir, Nitrox (21-40% Oxygen)—
APNEA modeYes—
Deep Stopsyes (using custom Gradient Factors)—
No fly timeYes—
Safety Stopyes (customizable off/3min/5min)—
Dive planneryes (Basic NDL & Gas Planner)—
Nitrox supportYes—
Alerts & alarmsyes (vibration only)—
Single-gas modeYes—
3-axis dive compassyes with adjustable heading, quick change to 90R, 90L, and Reciprocal. Indicates degrees and direction back to set heading.—
Auto start/end diveYes—
Decompression modelBühlmann ZHL-16c with Gradient Factors—
Missed Deco Lockoutyes (can be disabled prior to dive with user acknowledgement)—
Custom end-dive timeoutyes (20 sec to 10 min)—
Customizable conservatismyes (Low/Medium/High)—
Surface diver status widgetyes (Surface Interval, no fly time, N2 loading, CNS, OTU, and Tissue Compartment status)—
Automatic altitude adjustmentYes—
Dive ascent/descent rate indicatorYes—
Dive activity maximum operating depth40 meters—
Sync dive log to Garmin Dive™ Mobile appYes—
Automatically saves dive entry and exit locationsYes—
Boating Features
Wearable trolling motor remoteYes—
Cycling Features
CoursesYesYes
Power guideYes—
MTB Grit & FlowYes—
Race an activityYesYes
Power meter compatibleYesYes
Advanced cycling dynamicsYes—
Power curve and % FTP workoutsYesYes
Compatible with Varia™ lightsYesYes
FTP (Functional Threshold Power)yes (with compatible accessory)—
Compatible with Varia headlight cameraYesYes
Speed and cadence sensor support (w/sensor)YesYes
Cycle Map (routable cycling-specific street map)Yes—
Bike lap and lap maximum power (with power sensor)YesYes
Compatible with Varia™ radar (rear-facing radar)YesYes
Compatible with Vector™ and Rally™ (power meters)YesYes
Compatible with Varia Vision™ (head-mounted display)YesYes
Alerts (triggers alarm when you reach goals including time, distance, heart rate or calories)YesYes
Golfing Features
PinPointerYes—
Swing TempoYes—
Custom targetsYes—
Tempo TrainingYes—
Virtual caddieYes—
Full vector mapYes—
Handicap scoringYes—
Tournament legalYes—
Digital scorecardYes—
Garmin AutoShot™Yes—
PlaysLike distanceYes—
Round timer/odometerYes—
Auto CourseView updatesYes—
Yardage to layups/doglegsYes—
Hazards and course targetsYes—
Pairs with Garmin Golf appYes—
Green View with manual pin positionYes—
Preloaded with 43,000 courses worldwideYes—
Green Contours (with Garmin Golf membership)Yes—
CT10 Automatic club tracking compatible (requires accessory)Yes—
Yardage to F/M/B (distance to front, middle and back of green)Yes—
Stat tracking (strokes, putts per round, greens and fairways hit)Yes—
Wind speed and direction (requires connection to Garmin Golf app)Yes—
Touch-targeting (touch target on display to see the distance to any point)Yes—
Measures shot distance (calculates exact yardage for shots from anywhere on course)automatic—
Running Features
Hill scoreYes—
Run workoutsYesYes
Running powerYesYes
Race predictorYesYes
Foot pod capableYesYes
Running dynamicsYesYes
Lactate thresholdyes (with compatible accessory)Yes
Grade-adjusted paceYesYes
Trail run auto climbYesYes
Performance conditionYesYes
Run/Walk/Stand detectionYesYes
Stride length (real time)YesYes
PacePro™ Pacing StrategiesYesYes
Vertical oscillation and ratioYesYes
Ground contact time and balanceyes (GCT balance with accessory)yes (with compatible accessory)
GPS-based distance, time and paceYesYes
Course- and weather-specific race predictorYesYes
Cadence (provides real-time number of steps per minute)YesYes
What You'll Love
TouchscreenYesYes
Display typeAMOLEDAMOLED (optional always-on mode)
Water rating10 ATM5 ATM
Garmin Pay™YesYes
Music storageYesYes
Garmin ECG AppYes—
LED flashlightYes—
Multi-band GPSYesYes
Training statusYesyes (improved)
Built-in mappingYes—
Training readinessYesYes
Pulse Ox blood oxygenYesyes (spot-check, and optional all-day acclimation and in sleep)
Sleep score and insightsYesYes
Battery life (smartwatch mode)Up to 10 days (4 days always-on)Up to 15 days
Make calls and send texts via voiceYes—
Activity Profiles
GymStrength, HIIT, Cardio, Elliptical Training, Stair Stepping, Floor Climbing, Indoor Rowing, Jump RopingStrength, HIIT, Cardio, Elliptical Training, Stair Stepping, Floor Climbing, Indoor Rowing, Jump Roping
DiveScuba Diving (single gas), Apnea Diving, Depth App—
SwimPool Swimming, Open Water SwimmingPool Swimming, Open Water Swimming
CyclingBiking, Road Biking, Mountain Biking, Gravel Biking, Bike Commuting, Bike Touring, eBiking, eMountain Biking, Indoor Biking, Cyclocross, BMXBiking, Mountain Biking, eBiking, eMountain Biking, Indoor Biking
WellnessWalking, Indoor Walking, Pilates, YogaWalking, Pilates, Yoga, Indoor Walking
MultisportSwimming/Running, TriathlonTriathlon
In the ringBoxing, Mixed Martial ArtsBoxing, Mixed Martial Arts
Team sportsBasketball, Volleyball, Field Hockey, Ice Hockey, Football/Soccer, American Football, Lacrosse, Rugby, Ultimate Disc, Cricket, Softball, BaseballBasketball, Volleyball, Field Hockey, Ice Hockey, Football/Soccer, American Football, Lacrosse, Rugby, Ultimate Disc, Cricket, Softball, Baseball
Motor sportsMotorcycling, Overlanding, Motocrossing, ATVing, Snowmobiling—
On the WaterStand Up Paddleboarding, Rowing, Kayaking, Surfing, Kiteboarding, Windsurfing, Fishing, Boating, Sailing, Water Skiing, Wakeboarding, Wakesurfing, Tubing, Snorkeling, WhitewaterStand Up Paddleboarding, Rowing
Racket sportsTennis, Pickleball, Badminton, Squash, Table Tennis, Padel, Platform Tennis, RacquetballTennis, Pickleball, Badminton, Squash, Table Tennis, Padel, Platform Tennis, Racquetball
Snow & winterSkiing, Snowboarding, Backcountry Snowboarding, XC Classic Skiing, XC Skate Skiing, Backcountry Skiing, Ice Skating, SnowshoeingSkiing, Snowboarding, XC Classic Skiing
Indoor runningTreadmill Running, Indoor Track Running, Virtual RunningTreadmill Running, Indoor Track Running, Virtual Running
Outdoor runningRunning, Outdoor Track Running, Trail Running, Ultra Running, Obstacle RacingRunning, Outdoor Track Running, Trail Running, Ultra Running
Outdoor recreationHiking, Rucking, Indoor Climbing, Bouldering, Climbing, Hunting, Horseback Riding, Golfing, Disc Golf, ArcheryHiking, Bouldering, Archery
Other activity profilesInline SkatingInline skating
Swimming Features
Pool swim workoutsYesYes
Critical swim speedYesYes
Time and distance alertsYesYes
Auto rest (pool swim only)YesYes
Drill logging (pool swim only)YesYes
Pacing alerts (pool swim only)YesYes
Countdown start (pool swim only)YesYes
Underwater wrist-based heart rateYesYes
"Repeat on" rest timer (pool swim only)YesYes
Basic rest timer (up from 0) (pool swim only)YesYes
Stroke type detection (freestyle, backstroke, breaststroke, butterfly) (pool swim only)YesYes
Pool swim metrics (lengths, distance, pace, stroke count, swim efficiency (SWOLF), calories)YesYes
Open-water swim metrics (distance, pace, stroke count/rate, stroke distance, swim efficiency (SWOLF), calories)YesYes
Heart rate from external HRM (real-time during rests, interval and session stats during rests, and automatic heart rate download post-swim)yes (with HRM-Tri, HRM-Swim, HRM-Pro or HRM-Pro Plus)yes (with HRM-Swim, HRM-Pro, HRM-Pro Plus or HRM 600)
Tactical Features
Dual grid coordinatesYes—
Outdoor Recreation
TidesYes—
Up AheadYesYes
Auto restYesYes
TracBack®YesYes
Sight 'N GoYes—
Tide glanceYes—
Back to startYesYes
Fish forecastYesyes (via Connect IQ™)
Explore NearbyYes—
UltraTrac modeYesYes
Vertical speedYesYes
GPS coordinatesYes—
Area calculationyes (via Connect IQ™)yes (via Connect IQ™)
Elevation profileYesYes
Projected waypointYesYes
Total ascent/descentYesYes
Future elevation plotYesYes
NextFork™ navigationYes—
Distance to destinationYesYes
Expedition GPS ActivityYes—
Sun and moon informationYesYes
Point-to-point navigationYesYes
Preloaded ski resort mapsYes—
ClimbPro™ Ascent PlannerYes—
Rest Timer (Ultra Run only)YesYes
Preloaded road and trail mapsyes (Sapphire Editions only)—
Bread crumb trail in real timeYesYes
Downloadable cartography supportYes—
Barometric trend indicator with Storm AlertYesYes
Daily Smart Features
StocksYesyes (optional Connect IQ app)
CalendarYesYes
PasscodeYesYes
ConnectivityBluetooth®, ANT+®, Wi-Fi®Bluetooth®, ANT+®, Wi-Fi®
Garmin ShareYesYes
Find My PhoneYesYes
Find My WatchYesYes
Voice commandYes—
Morning reportYesYes
Red shift modeYesYes
Weather forecastsYesYes
Smart NotificationsYesYes
Smart trainer controlYesYes
Smartphone compatibilityiPhone®, Android™iPhone®, Android™
Controls smartphone musicYesYes
On-device Connect IQ™ StoreYesYes
Plays and controls watch musicYesYes
Find My Phone during GPS activityYesYes
Pairs with Garmin Connect™ MobileYesYes
Compatible with Garmin Messenger appYesYes
Battery saver (customizable low power watch)YesYes
Bluetooth phone calling and voice assistant supportYes—
Realtime settings sync with Garmin Connect™ mobileYesYes
View images from notifications on watch (Android™ only)YesYes
Text response/reject phone call with text (Android™ only)YesYes
Connect IQ™ (downloadable watch faces, data fields and apps)YesYes
VIRB® Remote—Yes
Activity Tracking Features
TrueUp™YesYes
Move IQ™YesYes
Step counterYesYes
Floors climbedYesYes
Calories burnedYesYes
Distance traveledYesYes
Intensity minutesYesYes
Automatic rep countingYesYes
Garmin Connect™ Challenges appyes (optional Connect IQ app)yes (optional Connect IQ app)
Move alerts (displays on device after a period of inactivity)YesYes
Auto goal (learns your activity level and assigns a daily step goal)YesYes
Workout and Training Plans
HIIT workoutsYesYes
Yoga workoutsYesYes
Cardio workoutsYesYes
Pilates workoutsYesYes
Strength workoutsYesYes
Garmin Cycling CoachYesYes
Garmin Running CoachYesYes
Garmin Coach - StrengthYesYes
Garmin Running Coach ExpertsYesYes
On-screen workout animationsYesYes
On-screen workout muscle mapsYesYes
Garmin Coach - Prebuilt Cycling PlansYesYes
Daily Suggested Workout - Cycling (Pace and Heart Rate Based)YesYes
Daily Suggested Workout - Running (Pace and Heart Rate Based)YesYes
Health & Wellness Monitoring
Sleepyes (advanced)yes (advanced)
Hydrationyes (in Garmin Connect™ and optional Connect IQ™ widget)yes (in Garmin Connect™ and optional Connect IQ™ widget)
BreathworkYesYes
MeditationYesYes
Fitness ageYesYes
Sleep coachYesYes
Nap detectionYesYes
All-day stressYesYes
Women's healthyes (in Garmin Connect™ and optional Connect IQ™ widget)yes (in Garmin Connect™ and optional Connect IQ™ widget)
Health snapshotYesYes
Jet lag adviserYesYes
Respiration rateYesYes
Skin temperatureYes—
Resting heart rateYesYes
Breathing variationsYesYes
Abnormal heart rate alertsyes (high and low)yes (high and low)
Relaxation breathing timerYesYes
Body Battery™ energy monitorYesYes
Wrist-based heart rate (constant, every second)YesYes
Relaxation reminders—Yes
Safety and Tracking Features
AssistanceYesYes
Live Event SharingYesAndroid™ Only
Incident Detection during select activitiesYesYes
Incident detection alert on phone for wearablesYesYes
Training, Planning and Analysis Features
% HRRYesYes
% HR maxYesYes
HR zonesYesYes
HR alertsYesYes
ShortcutsYesYes
HRV statusYesYes
Load ratioYesYes
Manual lapYesYes
Rest timerYesYes
Auto max HRYesYes
Auto scrollYesYes
Finish timeYesYes
HR caloriesYesYes
Voice alertsYesYes
Custom alertsYesYes
Physio TrueUpYesYes
Recovery timeYesYes
Training loadYesYes
VO2 Max (Run)YesYes
Course guidanceYesYes
Endurance scoreYes—
Training effectYesYes
Virtual PartnerYesYes
Workout benefitYes—
Race an ActivityYesYes
Realtime staminaYes—
Advanced workoutsYesYes
Interval trainingYesYes
Race glance/widgetYesYes
Training load focusYesYes
VO2 Max (Trail Run)YesYes
Garmin Live SegmentsYes—
Strava Live SegmentsYes—
GPS speed and distanceYesYes
Configurable lap alertsYesYes
Customizable data pagesYesYes
Unified training statusYesYes
Touch and/or button lockYesYes
Activity history on watchYesYes
Multisport auto transitionYesYes
Downloadable training plansYesYes
Training effect (anaerobic)YesYes
Manual multisport activitiesYesYes
HRM running pace and distanceYesYes
Heat and altitude acclimationYes—
Customizable activity profilesYesYes
Trendline™ Popularity RoutingYes—
Auto Pause® automatic timer haltYesYes
Respiration rate (during exercise)yes (with compatible accessory)yes (with compatible accessory)
Auto Lap® interval tracking featureYesYes
Primary benefit (Training Effect labels)YesYes
Round-trip course creator (running/cycling)Yes—
Power Modes - customizable in-activity battery settingsYes—
HR broadcast (broadcasts HR data over ANT+® to paired devices)YesYes
Improved interval (includes open repeats, intervals data page, rest screen and auto detection)YesYes
HRV stress test (measures your heart rate variability while standing still, for 3 minutes, to provide you with an estimated stress level; the scale of this is 1 to 100; low scores indicate lower stress levels)yes (with compatible accessory)—
Improved recovery time—Yes
Kid Activity Tracking Features
Toe-to-Toe™ Challenges app—yes (optional Connect IQ Toe-to-Toe™ Challenges app)

Wrist Fit

Garmin Fenix 8 43mm AMOLED

Sits best on wrists ~45–61mm wide (≈ 12.0–16.3cm circumference).

Garmin Forerunner 265S

Sits best on wrists ~44–60mm wide (≈ 11.7–16.0cm circumference).

Frequently Asked Questions

Is the Garmin Fenix 8 43mm AMOLED bigger than the Garmin Forerunner 265S?

The Garmin Fenix 8 43mm AMOLED is bigger — 43mm vs 41.7mm case width.

Which fits a smaller wrist better, the Garmin Fenix 8 43mm AMOLED or the Garmin Forerunner 265S?

The Garmin Fenix 8 43mm AMOLED suits wrists around 45–61mm wide, and the Garmin Forerunner 265S around 44–60mm. The one with the smaller lower bound is the safer pick for a small wrist.

Can I see the Garmin Fenix 8 43mm AMOLED and Garmin Forerunner 265S side by side at true scale?

Yes — the schematics and photos above show both watches at matched scale, and our fit tool overlays each on your wrist width.

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