Garmin
Forerunner 170 vs Forerunner 70
Size, specs & wrist fit compared
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Which one fits you
Both need much the same wrist — roughly 45–61mm across the flat of the wrist. Neither will fit where the other won't, so decide on thickness, weight and features instead.
The Forerunner 170 and Forerunner 70 share a near-identical 42.6mm case, so wrist presence comes down to thickness, lug-to-lug and weight.
The Forerunner 170 is thinner than 84% of the 314 43mm watches we hold thickness for, the Forerunner 70 than 84% — so both wear flatter than their widths suggest.
The Forerunner 170 is 1g heavier than the Forerunner 70. Both are circular.
Forerunner 170
Forerunner 70
Switch or add watches
Garmin
Forerunner 170
Garmin
Forerunner 70
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.
Lay your arm flat on a table, palm facing up
Measure across the flat top of your wrist (not the circumference)
Measure at the point where you wear your watch — typically just below the wrist bone
Wrist width ≠ circumference. We need the flat width across the top of your wrist where the watch sits, not how far around.
Garmin Forerunner 170
Case 42.6mm · Lug-to-lug 42.6mm · Thickness 11.9mm · 41g
Balanced Fit
42.6mm on a 55mm wrist
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.
- 1. Lay your arm flat, palm up.
- 2. Measure the flat width across the top of your wrist — not the circumference.
- 3. Measure where you wear it, just below the wrist bone.
Leather: Attaches at the lugs, so the case back rests on your skin. Thins and softens with wear. The default: depth about seven tenths of the width. Typical figures, not this model’s own.
Show the measurementsHide 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)
Garmin Forerunner 70
Case 42.6mm · Lug-to-lug 42.6mm · Thickness 11.9mm · 40g
Balanced Fit
42.6mm on a 55mm wrist
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.
- 1. Lay your arm flat, palm up.
- 2. Measure the flat width across the top of your wrist — not the circumference.
- 3. Measure where you wear it, just below the wrist bone.
Leather: Attaches at the lugs, so the case back rests on your skin. Thins and softens with wear. The default: depth about seven tenths of the width. Typical figures, not this model’s own.
Show the measurementsHide 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 wrist40g
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.
- Garmin Forerunner 17042.6mm · 11.9mm thick
- Garmin Forerunner 7042.6mm · 11.9mm thick
3D preview
Forerunner 170 vs Forerunner 70 on a wrist
Sized to your own wrist, turned any way you like.
Shapes are built from published measurements, not manufacturer 3D models — accurate proportions, generic dial.
Battery life compared
Furthest apart in Smartwatch mode, where the 70 lasts 1.3× as long as the 170 (13 days against 10 days).
17070
Smartwatch
10 days13 days
Specifications
The short version
7 key specs| Spec | GarminForerunner 170 | GarminForerunner 70 |
|---|---|---|
| Case Width | 42.6mm | 42.6mm |
| Thickness | 11.9mm | 11.9mm |
| Weight | 41g | 40g |
| Shape | Circular | Circular |
| Display type | AMOLED (optional always-on mode) | AMOLED (optional always-on mode) |
| 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 | Smartwatch mode: Up to 13 days (5 days display always-on) Battery Saver Smartwatch mode: Up to 28 days GPS-Only GNSS mode: Up to 23 hours All-Systems GNSS mode: Up to 16 hours See Details |
| Released | 2026 | 2026 |
Every specification
228 specs| Spec | Garmin Forerunner 170 | Garmin Forerunner 70 |
|---|---|---|
| Overview | ||
| Family | Garmin | Garmin |
| General | ||
| Weight | 41 g | 40 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 | Smartwatch mode: Up to 13 days (5 days display always-on) Battery Saver Smartwatch mode: Up to 28 days GPS-Only GNSS mode: Up to 23 hours All-Systems GNSS mode: Up to 16 hours See Details |
| Battery type | Lithium ion | Lithium ion |
| Display Size | 1.2" (30.4 mm) diameter | 1.2" (30.4 mm) diameter |
| Color display | Yes | Yes |
| Lens material | chemically strengthened glass | chemically strengthened glass |
| Physical size | 42.6 x 42.6 x 11.9 mm Fits wrists with a circumference of 126-203 mm | 42.6 x 42.6 x 11.9 mm Fits wrists with a circumference of 126-203 mm |
| Bezel material | fiber-reinforced polymer | fiber-reinforced polymer |
| Memory/History | 4 GB | 512 MB |
| Strap material | silicone | silicone |
| Charging method | Garmin proprietary plug charger | Garmin proprietary plug charger |
| Large font option | Yes | Yes |
| Display resolution | 390 x 390 pixels | 390 x 390 pixels |
| Quick Release bands | yes (20 mm, Industry standard) | yes (20 mm, Industry standard) |
| Sensors | ||
| Stocks | Yes | Yes |
| Calendar | Yes | Yes |
| Passcode | Yes | Yes |
| Calculator | Yes | Yes |
| Color shift | Yes | Yes |
| Connectivity | Bluetooth®, ANT+® | Bluetooth®, ANT+® |
| Garmin Share | Yes | Yes |
| Hourly alert | Yes | Yes |
| Color filters | Yes | Yes |
| Find My Phone | Yes | Yes |
| Evening report | Yes | Yes |
| Morning report | Yes | Yes |
| Red shift mode | Yes | Yes |
| Weather forecasts | Yes | Yes |
| Smart Notifications | Yes | Yes |
| Smart trainer control | Yes | — |
| Smartphone compatibility | iPhone®, Android™ | iPhone®, Android™ |
| Controls smartphone music | Yes | Yes |
| On-device Connect IQ™ Store | Yes | Yes |
| Find My Phone during GPS activity | Yes | Yes |
| Pairs with Garmin Connect™ Mobile | Yes | Yes |
| Compatible with Garmin Messenger app | Yes | Yes |
| Find My Garmin (helps locate lost device) | Yes | Yes |
| Battery saver (customizable low power watch) | Yes | Yes |
| Realtime settings sync with Garmin Connect™ mobile | Yes | Yes |
| View images from notifications on watch (Android™ only) | Yes | Yes |
| Text response/reject phone call with text (Android™ only) | Yes | Yes |
| Connect IQ™ (downloadable watch faces, data fields and apps) | Yes | Yes |
| Variant | ||
| Color | Black with Black/Amp Yellow Band | Black |
| Available Colors | Black with Black/Amp Yellow Band; Whitestone with Whitestone/Cloud Blue Band | Citron; Whitestone; Black; Tidal Blue; Soft Pink; Cool Lavender |
| Clock Features | ||
| Sleep | yes (advanced) | yes (advanced) |
| Hydration | yes (in Garmin Connect™ and optional Connect IQ™ widget) | yes (in Garmin Connect™ and optional Connect IQ™ widget) |
| Breathwork | Yes | Yes |
| Fitness age | Yes | Yes |
| Sleep coach | Yes | Yes |
| Health status | Yes | Yes |
| Nap detection | Yes | Yes |
| All-day stress | Yes | Yes |
| Women's health | yes (in Garmin Connect™ and optional Connect IQ™ widget) | yes (in Garmin Connect™ and optional Connect IQ™ widget) |
| Health snapshot | Yes | Yes |
| Respiration rate | Yes | Yes |
| Lifestyle logging | Yes | Yes |
| Resting heart rate | Yes | Yes |
| Breathing variations | Yes | Yes |
| Relaxation reminders | Yes | Yes |
| Abnormal heart rate alerts | yes (high and low) | yes (high and low) |
| Relaxation breathing timer | Yes | Yes |
| Body Battery™ energy monitor | Yes | Yes |
| Heart rate (constant, every second) | Yes | Yes |
| Cycling Features | ||
| Pool swim workouts | Yes | Yes |
| Time and distance alerts | Yes | Yes |
| Auto rest (pool swim only) | Yes | Yes |
| Drill logging (pool swim only) | Yes | Yes |
| Countdown start (pool swim only) | Yes | Yes |
| Underwater wrist-based heart rate | Yes | Yes |
| "Repeat on" rest timer (pool swim only) | Yes | Yes |
| Basic rest timer (up from 0) (pool swim only) | Yes | Yes |
| Stroke type detection (freestyle, backstroke, breaststroke, butterfly) (pool swim only) | Yes | Yes |
| Pool swim metrics (lengths, distance, pace, stroke count, swim efficiency (SWOLF), calories) | Yes | Yes |
| Open-water swim metrics (distance, pace, stroke count/rate, stroke distance, swim efficiency (SWOLF), calories) | Yes | — |
| Heart rate from external HRM (real-time during rests, interval and session stats during rests, and automatic heart rate download post-swim) | Yes | Yes |
| Running Features | ||
| Auto rest | Yes | Yes |
| UltraTrac mode | Yes | Yes |
| Vertical speed | Yes | — |
| Elevation profile | Yes | — |
| Total ascent/descent | Yes | — |
| Future elevation plot | Yes | Yes |
| Distance to destination | Yes | Yes |
| Sun and moon information | Yes | Yes |
| Rest Timer (Ultra Run only) | Yes | Yes |
| What You'll Love | ||
| Timer | Yes | Yes |
| Stopwatch | Yes | Yes |
| Time/date | Yes | Yes |
| Alarm clock | Yes | Yes |
| Touchscreen | Yes | Yes |
| Display type | AMOLED (optional always-on mode) | AMOLED (optional always-on mode) |
| Water rating | 5 ATM | 5 ATM |
| GPS Time Sync | Yes | Yes |
| Garmin Pay™ | Yes | — |
| Training status | Yes | Yes |
| Smart wake alarm | Yes | Yes |
| Training readiness | Yes | Yes |
| Sunrise/sunset times | Yes | Yes |
| Pulse Ox blood oxygen | yes (spot-check, and optional all-day and in sleep) | yes (spot-check, and optional all-day and in sleep) |
| Sleep score and insights | Yes | Yes |
| Automatic daylight saving time | Yes | Yes |
| Battery life (smartwatch mode) | Up to 10 days | Up to 13 days |
| Activity Profiles | ||
| Assistance | Yes | Yes |
| Live Event Sharing | Android™ Only | Android™ Only |
| Incident Detection during select activities | Yes | Yes |
| Incident detection alert on phone for wearables | Yes | Yes |
| Outdoor Recreation | ||
| Up Ahead | Yes | Yes |
| TracBack® | Yes | Yes |
| Back to start | Yes | Yes |
| Point-to-point navigation | Yes | Yes |
| Bread crumb trail in real time | Yes | Yes |
| Daily Smart Features | ||
| HIIT workouts | Yes | Yes |
| Yoga workouts | Yes | Yes |
| Cardio workouts | Yes | Yes |
| Pilates workouts | Yes | Yes |
| Strength workouts | Yes | Yes |
| Garmin Cycling Coach | Yes | — |
| Garmin Running Coach | Yes | Yes |
| Garmin fitness coach | Yes | Yes |
| Garmin Coach - Strength | Yes | Yes |
| Garmin Running Coach Experts | Yes | Yes |
| On-screen workout muscle maps | Yes | Yes |
| Garmin Coach - Prebuilt Cycling Plans | Yes | Yes |
| Daily Suggested Workout - Running (Pace and Heart Rate Based) | Yes | Yes |
| Mapping & Navigation | ||
| Courses | Yes | Yes |
| Race an activity | Yes | Yes |
| Power meter compatible | Yes | — |
| Compatible with Varia™ lights | Yes | Yes |
| Compatible with Varia headlight camera | Yes | Yes |
| Speed and cadence sensor support (w/sensor) | Yes | Yes |
| Bike lap and lap maximum power (with power sensor) | Yes | — |
| Compatible with Varia™ radar (rear-facing radar) | Yes | Yes |
| Compatible with Vector™ and Rally™ (power meters) | Yes | — |
| Alerts (triggers alarm when you reach goals including time, distance, heart rate or calories) | Yes | Yes |
| Activity Tracking Features | ||
| % HRR | Yes | Yes |
| % HR max | Yes | Yes |
| HR zones | Yes | Yes |
| HR alerts | Yes | Yes |
| Shortcuts | Yes | Yes |
| HRV status | Yes | Yes |
| Load ratio | Yes | Yes |
| Manual lap | Yes | Yes |
| Rest timer | Yes | Yes |
| Auto max HR | Yes | Yes |
| Finish time | Yes | Yes |
| HR calories | Yes | Yes |
| Voice alerts | Yes | Yes |
| Custom alerts | Yes | Yes |
| Physio TrueUp | Yes | Yes |
| Recovery time | Yes | Yes |
| Training load | Yes | Yes |
| VO2 Max (Run) | Yes | Yes |
| Course guidance | Yes | Yes |
| Training effect | Yes | Yes |
| Race an Activity | Yes | Yes |
| Advanced workouts | Yes | Yes |
| Interval training | Yes | Yes |
| Race glance/widget | Yes | Yes |
| Training load focus | Yes | Yes |
| VO2 Max (Trail Run) | Yes | Yes |
| GPS speed and distance | Yes | Yes |
| Configurable lap alerts | Yes | Yes |
| Customizable data pages | Yes | Yes |
| Unified training status | Yes | Yes |
| Touch and/or button lock | Yes | Yes |
| Activity history on watch | Yes | Yes |
| Downloadable training plans | Yes | Yes |
| Training effect (anaerobic) | Yes | Yes |
| HRM running pace and distance | Yes | Yes |
| Customizable activity profiles | Yes | Yes |
| Auto Pause® automatic timer halt | Yes | Yes |
| Respiration rate (during exercise) | yes (with compatible accessory) | yes (with compatible accessory) |
| Auto Lap® interval tracking feature | Yes | Yes |
| Primary benefit (Training Effect labels) | Yes | Yes |
| HR broadcast (broadcasts HR data over ANT+® to paired devices) | Yes | Yes |
| Improved interval (includes open repeats, intervals data page, rest screen and auto detection) | Yes | Yes |
| Workout and Training Plans | ||
| Gym | Strength, HIIT, Cardio, Elliptical Training, Stair Stepping,, Floor Climbing, Indoor Rowing, Jump Roping | Strength, HIIT, Cardio, Elliptical Training, Stair Stepping, Indoor Rowing, Jump Roping |
| Swim | Pool Swimming, Open Water Swimming | Pool Swimming |
| Cycling | Biking, Road Biking, Mountain Biking, Gravel Biking, Bike Commuting, Bike Touring, eBiking, eMountain Biking, Indoor Biking, Cyclocross | 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 | Walking, Pilates, Yoga , Indoor Walking, Mobility, Breathwork |
| In the ring | Boxing, Mixed Martial Arts | Boxing, Mixed Martial Arts |
| Team sports | Basketball, Volleyball, Field Hockey, Ice Hockey, Football/Soccer, American Football, Lacrosse, Rugby, Ultimate Disc, Cricket, Softball, Baseball | Basketball, Volleyball, Field Hockey, Ice Hockey, Football/Soccer, American Football, Lacrosse, Rugby, Ultimate Disc, Cricket, Softball, Baseball |
| Motor sports | Motorcycling, Overlanding, Motocrossing, ATVing, Snowmobiling | Motorcycling, Overlanding, Motocrossing, ATVing, Snowmobiling |
| On the water | Stand Up Paddleboarding, Rowing, Kayaking, Snorkeling | Stand Up Paddleboarding, Rowing, Kayaking, Snorkeling |
| Racket sports | Tennis, Pickleball, Badminton, Squash, Table Tennis, Padel, Platform Tennis, Racquetball | Tennis, Pickleball, Badminton, Squash, Table Tennis, Padel, Platform Tennis, Racquetball |
| Indoor running | Treadmill Running, Indoor Track Running, Virtual Running | Treadmill Running, Indoor Track Running, Virtual Running |
| Outdoor running | Running, Outdoor Track Running, Trail Running, Ultra Running, Obstacle Racing | Running, Outdoor Track Running, Trail Running, Ultra Running, Obstacle Racing |
| Snow and winter | Skiing, Snowboarding, XC Classic Skiing, XC Skate Skiing, Ice Skating, Snowshoeing | Skiing, Snowboarding, XC Classic Skiing, XC Skate Skiing, Ice Skating, Snowshoeing |
| Outdoor recreation | Hiking, Rucking, Mountaineering, Horseback Riding, Disc Golf, Archery | Hiking, Rucking, Mountaineering, Horseback Riding, Disc Golf, Archery |
| Other activity profiles | Inline Skating | Inline Skating |
| Health & Wellness Monitoring | ||
| GPS | Yes | Yes |
| Compass | Yes | — |
| GLONASS | Yes | Yes |
| Galileo | Yes | Yes |
| Gyroscope | Yes | — |
| Thermometer | Yes | — |
| Accelerometer | Yes | Yes |
| Ambient light sensor | Yes | Yes |
| Barometric altimeter | Yes | — |
| Pulse Ox Blood Oxygen Saturation Monitor | Yes | Yes |
| Garmin Elevate™ wrist heart rate monitor | Yes | Yes |
| Safety and Tracking Features | ||
| TrueUp™ | Yes | Yes |
| Move IQ™ | Yes | Yes |
| Step counter | Yes | Yes |
| Floors climbed | Yes | — |
| Calories burned | Yes | Yes |
| Distance traveled | Yes | Yes |
| Intensity minutes | Yes | Yes |
| Automatic rep counting | Yes | Yes |
| Move Alert movement options | Yes | Yes |
| Garmin Connect™ Challenges app | yes (optional Connect IQ app) | yes (optional Connect IQ app) |
| Move alerts (displays on device after a period of inactivity) | Yes | Yes |
| Auto goal (learns your activity level and assigns a daily step goal) | Yes | Yes |
| Training, Planning and Analysis Features | ||
| Run workouts | Yes | Yes |
| Quick workout | Yes | Yes |
| Running power | Yes | Yes |
| Race predictor | Yes | Yes |
| Foot pod capable | Yes | Yes |
| Running dynamics | Yes | Yes |
| Grade-adjusted pace | Yes | — |
| Run/Walk/Stand detection | Yes | Yes |
| Stride length (real time) | Yes | Yes |
| PacePro™ Pacing Strategies | Yes | Yes |
| Vertical oscillation and ratio | Yes | Yes |
| Ground contact time and balance | yes (GCT balance with accessory) | yes (GCT balance with accessory) |
| GPS-based distance, time and pace | Yes | Yes |
| Course- and weather-specific race predictor | Yes | Yes |
| Cadence (provides real-time number of steps per minute) | Yes | Yes |
Wrist Fit
Garmin Forerunner 170
Sits best on wrists ~45–61mm wide (≈ 12.0–16.3cm circumference).
Garmin Forerunner 70
Sits best on wrists ~45–61mm wide (≈ 12.0–16.3cm circumference).
Frequently Asked Questions
Is the Garmin Forerunner 170 bigger than the Garmin Forerunner 70?
Both have a 42.6mm case. Compare their thickness and lug-to-lug above to judge wrist presence.
Which fits a smaller wrist better, the Garmin Forerunner 170 or the Garmin Forerunner 70?
The Garmin Forerunner 170 suits wrists around 45–61mm wide, and the Garmin Forerunner 70 around 45–61mm. The one with the smaller lower bound is the safer pick for a small wrist.
Can I see the Garmin Forerunner 170 and Garmin Forerunner 70 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.