WatchFitTool
Garmin Forerunner 170 — case dimensions and design

Garmin · 2026

Forerunner 170Size, Dimensions & Wrist Fit

Case Width

42.6mm

Thickness

11.9mm

Battery

10 days

Weight

41g

The Garmin Forerunner 170 sits best on flat wrist widths of about 45–61mm (≈ 12.0–16.3cm wrist circumference). Adjust the slider below to check your wrist.

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The Forerunner 170 in short

The figures that decide whether this watch suits you, pulled out of the full specification sheet further down.

  • Rated for 10 days of use per charge.
  • Water rated to 5 ATM.
  • 11.9mm thick. Thinner than 84% of 43mm watches, so it slides under a cuff more easily than most of its size.
  • 1.2" (30.4 mm) diameter AMOLED (optional always-on mode) display.
  • chemically strengthened glass case, chemically strengthened glass glass.

Does the Forerunner 170 fit your wrist?

Drag the slider to your wrist width and see the Forerunner 170 overlaid at true scale. Lug-to-lug — not case diameter — decides whether a watch overhangs your wrist.

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 Forerunner 170

Case 42.6mm · Lug-to-lug 42.6mm · Thickness 11.9mm · 41g

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Balanced Fit

42.6mm on a 55mm wrist

10:09TUE 12lug to lug 42.6mmyour 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 42.6mm, 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 wrist6.2mm spare each side

    Comfortable, with visible skin either side.

  • Off the wrist11.9mm off the skin

    Normal sports-watch height for a wrist this size. (11.9mm case, back against the skin)

  • How it seats~4.2mm under the rim

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

  • Weight on the wrist41g

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

Happy with the fit? Check current availability for the Forerunner 170.

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2D Dimension Schematics

The Forerunner 170 drawn to scale — from above, and in profile against the wrist.

Highlight
From above — true scale
From the side — how far it sits off the wrist
  • Garmin Forerunner 17042.6mm · 11.9mm thick

3D preview

Garmin Forerunner 170 on a wrist

On an arm sized to your own wrist — the view a product photo never gives you.

Open 3D try-on

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

Forerunner 170 battery life

The runtime the manufacturer publishes for everyday use.

  • Smartwatch10 days
Lithium ion

How the Forerunner 170 ranks on battery

Against the 296 Garmin watches in our database, ranked on each figure Garmin publishes.

  • Everyday use10 days#211 of 285
  • GPS tracking20 hours#174 of 267
  • Power save19 days#24 of 37
See all 296 Garmin watches ranked by battery life

Forerunner 170 specifications

The figures that decide a purchase, followed by every line Garmin publishes.

Battery life
Smartwatch mode: Up to 10 days (4 days display always-on) Battery Saver Smartwatch mode: Up to 19 days GPS-Only GNSS mode: Up to 20 hours All-Systems GNSS mode: Up to 14 hours See Details
Display
1.2" (30.4 mm) diameter
Resolution
390 x 390 pixels
Water rating
5 ATM
Bezel
fiber-reinforced polymer
Glass
chemically strengthened glass
Strap
silicone
Storage
4 GB
Charging
Garmin proprietary plug charger

Full specification sheet

228 published lines across 17 groups, unedited

Overview

Family
Garmin

General

Weight
41 g
Battery life
Smartwatch mode: Up to 10 days (4 days display always-on) Battery Saver Smartwatch mode: Up to 19 days GPS-Only GNSS mode: Up to 20 hours All-Systems GNSS mode: Up to 14 hours See Details
Battery type
Lithium ion
Display Size
1.2" (30.4 mm) diameter
Color display
Lens material
chemically strengthened glass
Physical size
42.6 x 42.6 x 11.9 mm Fits wrists with a circumference of 126-203 mm
Bezel material
fiber-reinforced polymer
Memory/History
4 GB
Strap material
silicone
Charging method
Garmin proprietary plug charger
Large font option
Display resolution
390 x 390 pixels
Quick Release bands
yes (20 mm, Industry standard)

Sensors

Stocks
Calendar
Passcode
Calculator
Color shift
Connectivity
Bluetooth®, ANT+®
Garmin Share
Hourly alert
Color filters
Find My Phone
Evening report
Morning report
Red shift mode
Weather forecasts
Smart Notifications
Smart trainer control
Smartphone compatibility
iPhone®, Android™
Controls smartphone music
On-device Connect IQ™ Store
Find My Phone during GPS activity
Pairs with Garmin Connect™ Mobile
Compatible with Garmin Messenger app
Find My Garmin (helps locate lost device)
Battery saver (customizable low power watch)
Realtime settings sync with Garmin Connect™ mobile
View images from notifications on watch (Android™ only)
Text response/reject phone call with text (Android™ only)
Connect IQ™ (downloadable watch faces, data fields and apps)

Variant

Color
Black with Black/Amp Yellow Band
Available Colors
Black with Black/Amp Yellow Band; Whitestone with Whitestone/Cloud Blue Band

Clock Features

Sleep
yes (advanced)
Hydration
yes (in Garmin Connect™ and optional Connect IQ™ widget)
Breathwork
Fitness age
Sleep coach
Health status
Nap detection
All-day stress
Women's health
yes (in Garmin Connect™ and optional Connect IQ™ widget)
Health snapshot
Respiration rate
Lifestyle logging
Resting heart rate
Breathing variations
Relaxation reminders
Abnormal heart rate alerts
yes (high and low)
Relaxation breathing timer
Body Battery™ energy monitor
Heart rate (constant, every second)

Cycling Features

Pool swim workouts
Time and distance alerts
Auto rest (pool swim only)
Drill logging (pool swim only)
Countdown start (pool swim only)
Underwater wrist-based heart rate
"Repeat on" rest timer (pool swim only)
Basic rest timer (up from 0) (pool swim only)
Stroke type detection (freestyle, backstroke, breaststroke, butterfly) (pool swim only)
Pool swim metrics (lengths, distance, pace, stroke count, swim efficiency (SWOLF), calories)
Open-water swim metrics (distance, pace, stroke count/rate, stroke distance, swim efficiency (SWOLF), calories)
Heart rate from external HRM (real-time during rests, interval and session stats during rests, and automatic heart rate download post-swim)

Running Features

Auto rest
UltraTrac mode
Vertical speed
Elevation profile
Total ascent/descent
Future elevation plot
Distance to destination
Sun and moon information
Rest Timer (Ultra Run only)

What You'll Love

Timer
Stopwatch
Time/date
Alarm clock
Touchscreen
Display type
AMOLED (optional always-on mode)
Water rating
5 ATM
GPS Time Sync
Garmin Pay™
Training status
Smart wake alarm
Training readiness
Sunrise/sunset times
Pulse Ox blood oxygen
yes (spot-check, and optional all-day and in sleep)
Sleep score and insights
Automatic daylight saving time
Battery life (smartwatch mode)
Up to 10 days

Activity Profiles

Assistance
Live Event Sharing
Android™ Only
Incident Detection during select activities
Incident detection alert on phone for wearables

Outdoor Recreation

Up Ahead
TracBack®
Back to start
Point-to-point navigation
Bread crumb trail in real time

Daily Smart Features

HIIT workouts
Yoga workouts
Cardio workouts
Pilates workouts
Strength workouts
Garmin Cycling Coach
Garmin Running Coach
Garmin fitness coach
Garmin Coach - Strength
Garmin Running Coach Experts
On-screen workout muscle maps
Garmin Coach - Prebuilt Cycling Plans
Daily Suggested Workout - Running (Pace and Heart Rate Based)

Mapping & Navigation

Courses
Race an activity
Power meter compatible
Compatible with Varia™ lights
Compatible with Varia headlight camera
Speed and cadence sensor support (w/sensor)
Bike lap and lap maximum power (with power sensor)
Compatible with Varia™ radar (rear-facing radar)
Compatible with Vector™ and Rally™ (power meters)
Alerts (triggers alarm when you reach goals including time, distance, heart rate or calories)

Activity Tracking Features

% HRR
% HR max
HR zones
HR alerts
Shortcuts
HRV status
Load ratio
Manual lap
Rest timer
Auto max HR
Finish time
HR calories
Voice alerts
Custom alerts
Physio TrueUp
Recovery time
Training load
VO2 Max (Run)
Course guidance
Training effect
Race an Activity
Advanced workouts
Interval training
Race glance/widget
Training load focus
VO2 Max (Trail Run)
GPS speed and distance
Configurable lap alerts
Customizable data pages
Unified training status
Touch and/or button lock
Activity history on watch
Downloadable training plans
Training effect (anaerobic)
HRM running pace and distance
Customizable activity profiles
Auto Pause® automatic timer halt
Respiration rate (during exercise)
yes (with compatible accessory)
Auto Lap® interval tracking feature
Primary benefit (Training Effect labels)
HR broadcast (broadcasts HR data over ANT+® to paired devices)
Improved interval (includes open repeats, intervals data page, rest screen and auto detection)

Workout and Training Plans

Gym
Strength, HIIT, Cardio, Elliptical Training, Stair Stepping,, Floor Climbing, Indoor Rowing, Jump Roping
Swim
Pool Swimming, Open Water Swimming
Cycling
Biking, Road Biking, Mountain Biking, Gravel Biking, Bike Commuting, Bike Touring, eBiking, eMountain Biking, Indoor Biking, Cyclocross
Wellness
Walking, Pilates, Yoga , Indoor Walking, Mobility, Breathwork
In the ring
Boxing, Mixed Martial Arts
Team sports
Basketball, Volleyball, Field Hockey, Ice Hockey, Football/Soccer, American Football, Lacrosse, Rugby, Ultimate Disc, Cricket, Softball, Baseball
Motor sports
Motorcycling, Overlanding, Motocrossing, ATVing, Snowmobiling
On the water
Stand Up Paddleboarding, Rowing, Kayaking, Snorkeling
Racket sports
Tennis, Pickleball, Badminton, Squash, Table Tennis, Padel, Platform Tennis, Racquetball
Indoor running
Treadmill Running, Indoor Track Running, Virtual Running
Outdoor running
Running, Outdoor Track Running, Trail Running, Ultra Running, Obstacle Racing
Snow and winter
Skiing, Snowboarding, XC Classic Skiing, XC Skate Skiing, Ice Skating, Snowshoeing
Outdoor recreation
Hiking, Rucking, Mountaineering, Horseback Riding, Disc Golf, Archery
Other activity profiles
Inline Skating

Health & Wellness Monitoring

GPS
Compass
GLONASS
Galileo
Gyroscope
Thermometer
Accelerometer
Ambient light sensor
Barometric altimeter
Pulse Ox Blood Oxygen Saturation Monitor
Garmin Elevate™ wrist heart rate monitor

Safety and Tracking Features

TrueUp™
Move IQ™
Step counter
Floors climbed
Calories burned
Distance traveled
Intensity minutes
Automatic rep counting
Move Alert movement options
Garmin Connect™ Challenges app
yes (optional Connect IQ app)
Move alerts (displays on device after a period of inactivity)
Auto goal (learns your activity level and assigns a daily step goal)

Training, Planning and Analysis Features

Run workouts
Quick workout
Running power
Race predictor
Foot pod capable
Running dynamics
Grade-adjusted pace
Run/Walk/Stand detection
Stride length (real time)
PacePro™ Pacing Strategies
Vertical oscillation and ratio
Ground contact time and balance
yes (GCT balance with accessory)
GPS-based distance, time and pace
Course- and weather-specific race predictor
Cadence (provides real-time number of steps per minute)

Forerunner 170 — Frequently Asked Questions

Will the Garmin Forerunner 170 fit my wrist?

The Garmin Forerunner 170 looks balanced on flat wrist widths of roughly 45–61mm (about 12.0–16.3cm circumference). Drag the slider above to check it against your own measurement.

How long does the Garmin Forerunner 170 battery last?

Garmin rates it at 10 days per charge in everyday use.

How does the Garmin Forerunner 170 battery compare with other Garmin watches?

At 10 days in everyday use it ranks #211 of the 285 Garmin watches in our database — below the middle of the range. The full ranking, including GPS and power-saving figures, is on our Garmin battery life comparison.

Is the Garmin Forerunner 170 thick for a 43mm watch?

At 11.9mm, thinner than 84% of 43mm watches, so it slides under a cuff more easily than most of its size. Thickness, not case width, is what decides whether a watch catches on a shirt cuff.

What other watches are the same size as the Garmin Forerunner 170?

OnePlus Watch 3 43mm, Oppo Watch X2 Mini, Omega Speedmaster Moonphase Stainless Steel / Black Meteorite / Bracelet, Zenith Defy Extreme Diver Shadow / Bracelet all sit within half a millimetre of the Garmin Forerunner 170's 42.6mm case, so they cover the same amount of wrist.

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