Apple Watch Ultra 3 vs Garmin Forerunner 170
Size, specs & wrist fit compared
As an Amazon Associate, WatchFitTool earns from qualifying purchases.
Which one fits you
On wrists narrower than about 52mm, the Garmin Forerunner 170 is the safer pick — it stays proportionate down to roughly 45mm, where the Apple Watch Ultra 3 starts to hang over the edge. Above 52mm both sit cleanly, and the Apple Watch Ultra 3 gives you more presence.
The Apple Watch Ultra 3 wears larger than the Garmin Forerunner 170 (44mm vs 42.6mm case), giving it more wrist presence — and needing a wider wrist to sit cleanly.
On the wrist the Garmin Forerunner 170 feels lighter (41g vs 61.8g, case only).
The Apple Watch Ultra 3 is thinner than 89% of the 44mm watches we track and the Garmin Forerunner 170 than 84% of the 43mm ones — so both wear flatter than their widths suggest.
The Apple Watch Ultra 3 is 1.4mm wider, 6.4mm longer, 0.1mm thicker and 20.8g heavier than the Garmin Forerunner 170.
Apple
Watch Ultra 3
Garmin
Forerunner 170
Switch or add watches
Apple
Watch Ultra 3
Garmin
Forerunner 170
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.
Apple Watch Ultra 3
Case 49.0mm · Lug-to-lug 49.0mm · Thickness 12.0mm · 62g
Sweet Spot
49mm on a 55mm wrist
Across the wrist it works — 3.0mm spare each side — but wide enough that the edge of the case back lifts clear of the skin.
On a 55mm wrist the sweet spot is 47–53mm lug to lug. This one is 49mm.
- 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 wrist3.0mm spare each side
Fills the wrist without reaching the edge.
- Off the wrist12.0mm off the skin
Normal sports-watch height for a wrist this size. (12.0mm case, back against the skin)
- How it seats~7.3mm under the rim
Wide enough that the edge of the case back lifts clear of the skin.
- Weight on the wrist62g
Substantial without being a burden — the usual weight of a steel watch on a wrist this size. (1.1g per mm of wrist)
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)
2D Dimension Schematics
Every case drawn to scale on a shared centre — from above, and in profile against the wrist.
- Apple Watch Ultra 344mm × 49mm · 12mm thick
- Garmin Forerunner 17042.6mm · 11.9mm thick
3D preview
Apple Watch Ultra 3 vs Garmin Forerunner 170 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 Garmin Forerunner 170 lasts 5.7× as long as the Apple Watch Ultra 3 (10 days against 42 hours).
Apple Watch Ultra 3Garmin Forerunner 170
Smartwatch
1.75 days10 daysBattery Saver
72 hours—
Specifications
The short version
7 key specs| Spec | AppleWatch Ultra 3 | GarminForerunner 170 |
|---|---|---|
| Case Width | 44mm | 42.6mm |
| Lug-to-Lug | 49mm | 42.6mm |
| Thickness | 12mm | 11.9mm |
| Weight | 61.8g | 41g |
| Shape | Rectangle | Circular |
| Display type | OLED/AMOLED | AMOLED (optional always-on mode) |
| Released | 2025 | 2026 |
Every specification
345 specs| Spec | Apple Watch Ultra 3 | Garmin Forerunner 170 |
|---|---|---|
| Design | ||
| width | 44 | — |
| height | 49 | — |
| volume | 25.87 cm³ | — |
| weight | 61.8 g | — |
| thickness | 12 | — |
| ATM rating | 10 ATM | — |
| resolution | 422 x 514 px | — |
| screen size | 1.98 inches | — |
| Display type | OLED/AMOLED | — |
| Has a display | Yes | — |
| pixel density | 326 ppi | — |
| water resistance | Waterproof | — |
| Always-On Display | Yes | — |
| has a touch screen | Yes | — |
| is designed for kids | No | — |
| waterproof depth rating | 100 m | — |
| Watch band is replaceable | Yes | — |
| Has sapphire glass display | Yes | — |
| maximum operating temperature | 55 °C | — |
| Ingress Protection (IP) rating | IPX6 | — |
| has branded damage-resistant glass | No | — |
| lowest potential operating temperature | -20 °C | — |
| Battery | ||
| charge time | 1.5 hours | — |
| battery life | 1.75 days | — |
| has wireless charging | Yes | — |
| has a removable battery | No | — |
| Has a solar power battery | No | — |
| has a rechargeable battery | Yes | — |
| battery life in power save mode | 72 hours | — |
| Sensors | ||
| has GPS | Yes | — |
| has a compass | Yes | — |
| Has a barometer | Yes | — |
| has a gyroscope | Yes | — |
| Has a cadence sensor | No | — |
| has an accelerometer | Yes | — |
| Monitors perspiration | No | — |
| Has a heart rate monitor | Yes | — |
| Has a temperature sensor | Yes | — |
| Monitors blood oxygenation levels | Yes | — |
| Stocks | — | Yes |
| Calendar | — | Yes |
| Passcode | — | Yes |
| Calculator | — | Yes |
| Color shift | — | Yes |
| Connectivity | — | Bluetooth®, ANT+® |
| Garmin Share | — | Yes |
| Hourly alert | — | Yes |
| Color filters | — | Yes |
| Find My Phone | — | Yes |
| Evening report | — | Yes |
| Morning report | — | Yes |
| Red shift mode | — | Yes |
| Weather forecasts | — | Yes |
| Smart Notifications | — | Yes |
| Smart trainer control | — | Yes |
| Smartphone compatibility | — | iPhone®, Android™ |
| Controls smartphone music | — | Yes |
| On-device Connect IQ™ Store | — | Yes |
| Find My Phone during GPS activity | — | Yes |
| Pairs with Garmin Connect™ Mobile | — | Yes |
| Compatible with Garmin Messenger app | — | Yes |
| Find My Garmin (helps locate lost device) | — | Yes |
| Battery saver (customizable low power watch) | — | Yes |
| Realtime settings sync with Garmin Connect™ mobile | — | Yes |
| View images from notifications on watch (Android™ only) | — | Yes |
| Text response/reject phone call with text (Android™ only) | — | Yes |
| Connect IQ™ (downloadable watch faces, data fields and apps) | — | Yes |
| Features | ||
| RAM | 2GB | — |
| release date | 2025-09-09 | — |
| Has a stopwatch | Yes | — |
| Has smart alarm | No | — |
| warranty period | 1 years | — |
| Has call control | Yes | — |
| Has silent alarm | Yes | — |
| has HRV tracking | Yes | — |
| internal storage | 64GB | — |
| measures VO2 max | Yes | — |
| Has notifications | Yes | — |
| Has ECG technology | Yes | — |
| Locates your phone | Yes | — |
| has a front camera | No | — |
| has fall detection | Yes | — |
| has voice commands | Yes | — |
| Acquires GPS faster | Yes | — |
| Has vibrating alerts | Yes | — |
| number of microphones | 1 | — |
| Can be used to answer calls | Yes | — |
| measures resting heart rate | Yes | — |
| has irregular heart rate warnings | Yes | — |
| has fast/slow heart rate notifications | Yes | — |
| Has a built-in camera remote control function | Yes | — |
| Connectivity | ||
| has NFC | Yes | — |
| SIM cards | 1 eSIM | — |
| Wi-Fi version | Wi-Fi 4 (802.11n) | — |
| supports ANT+ | No | — |
| supports Wi-Fi | Yes | — |
| supports Galileo | Yes | — |
| Bluetooth version | 5.3 | — |
| has a cellular module | Yes | — |
| Is compatible with iOS | Yes | — |
| Is compatible with Android | No | — |
| Miscellaneous | ||
| has aptX | No | — |
| Has passcode | Yes | — |
| Has auto pause | Yes | — |
| has crash detection | Yes | — |
| Is compatible with Windows | No | — |
| Is compatible with Mac OS X | No | — |
| has an external memory slot | No | — |
| Compatible with smart scales | Yes | — |
| has a battery level indicator | Yes | — |
| has a socket for a 3.5 mm audio jack | No | — |
| Compatible with external heart rate monitors | Yes | — |
| App & Software | ||
| Ad-free | Yes | — |
| Free app | Yes | — |
| Has coaching | No | — |
| Includes maps | Yes | — |
| Supports routes | Yes | — |
| Has achievements | Yes | — |
| Has goal setting | Yes | — |
| Has exercise diary | Yes | — |
| Predicts ovulation | Yes | — |
| Can be personalised | Yes | — |
| Has weight tracking | Yes | — |
| Predicts start date | Yes | — |
| Tracks water intake | Yes | — |
| Has inactivity alerts | Yes | — |
| Has period notifications | Yes | — |
| Has temperature tracking | Yes | — |
| Provides activity reports | Yes | — |
| Displays fertile window notifications | Yes | — |
| Counts how many calories you've burned | Yes | — |
| Activity tracking | ||
| Measures pace | Yes | — |
| Tracks distance | Yes | — |
| Tracks elevation | Yes | — |
| Designed for golf | No | — |
| Tracks your sleep | Yes | — |
| Tracks steps taken | Yes | — |
| Designed for diving | Yes | — |
| Has a route tracker | Yes | — |
| Has exercise tagging | Yes | — |
| Has multi-sport mode | Yes | — |
| Tracks calorie intake | No | — |
| Provides sleep reports | Yes | — |
| Detects activities automatically | Yes | — |
| Has a stroke counter for swimming | Yes | — |
| 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 | — | Yes |
| 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 | — | Yes |
| Display resolution | — | 390 x 390 pixels |
| Quick Release bands | — | yes (20 mm, Industry standard) |
| 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 | — | Yes |
| Fitness age | — | Yes |
| Sleep coach | — | Yes |
| Health status | — | Yes |
| Nap detection | — | Yes |
| All-day stress | — | Yes |
| Women's health | — | yes (in Garmin Connect™ and optional Connect IQ™ widget) |
| Health snapshot | — | Yes |
| Respiration rate | — | Yes |
| Lifestyle logging | — | Yes |
| Resting heart rate | — | Yes |
| Breathing variations | — | Yes |
| Relaxation reminders | — | Yes |
| Abnormal heart rate alerts | — | yes (high and low) |
| Relaxation breathing timer | — | Yes |
| Body Battery™ energy monitor | — | Yes |
| Heart rate (constant, every second) | — | Yes |
| Cycling Features | ||
| Pool swim workouts | — | Yes |
| Time and distance alerts | — | Yes |
| Auto rest (pool swim only) | — | Yes |
| Drill logging (pool swim only) | — | Yes |
| Countdown start (pool swim only) | — | Yes |
| Underwater wrist-based heart rate | — | Yes |
| "Repeat on" rest timer (pool swim only) | — | Yes |
| Basic rest timer (up from 0) (pool swim only) | — | Yes |
| Stroke type detection (freestyle, backstroke, breaststroke, butterfly) (pool swim only) | — | Yes |
| Pool swim metrics (lengths, distance, pace, stroke count, swim efficiency (SWOLF), calories) | — | 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 |
| Running Features | ||
| Auto rest | — | Yes |
| UltraTrac mode | — | Yes |
| Vertical speed | — | Yes |
| Elevation profile | — | Yes |
| Total ascent/descent | — | Yes |
| Future elevation plot | — | Yes |
| Distance to destination | — | Yes |
| Sun and moon information | — | Yes |
| Rest Timer (Ultra Run only) | — | Yes |
| What You'll Love | ||
| Timer | — | Yes |
| Stopwatch | — | Yes |
| Time/date | — | Yes |
| Alarm clock | — | Yes |
| Touchscreen | — | Yes |
| Display type | — | AMOLED (optional always-on mode) |
| Water rating | — | 5 ATM |
| GPS Time Sync | — | Yes |
| Garmin Pay™ | — | Yes |
| Training status | — | Yes |
| Smart wake alarm | — | Yes |
| Training readiness | — | Yes |
| Sunrise/sunset times | — | Yes |
| Pulse Ox blood oxygen | — | yes (spot-check, and optional all-day and in sleep) |
| Sleep score and insights | — | Yes |
| Automatic daylight saving time | — | Yes |
| Battery life (smartwatch mode) | — | Up to 10 days |
| Activity Profiles | ||
| Assistance | — | Yes |
| Live Event Sharing | — | Android™ Only |
| Incident Detection during select activities | — | Yes |
| Incident detection alert on phone for wearables | — | Yes |
| Outdoor Recreation | ||
| Up Ahead | — | Yes |
| TracBack® | — | Yes |
| Back to start | — | Yes |
| Point-to-point navigation | — | Yes |
| Bread crumb trail in real time | — | Yes |
| Daily Smart Features | ||
| HIIT workouts | — | Yes |
| Yoga workouts | — | Yes |
| Cardio workouts | — | Yes |
| Pilates workouts | — | Yes |
| Strength workouts | — | Yes |
| Garmin Cycling Coach | — | Yes |
| Garmin Running Coach | — | Yes |
| Garmin fitness coach | — | Yes |
| Garmin Coach - Strength | — | Yes |
| Garmin Running Coach Experts | — | Yes |
| On-screen workout muscle maps | — | Yes |
| Garmin Coach - Prebuilt Cycling Plans | — | Yes |
| Daily Suggested Workout - Running (Pace and Heart Rate Based) | — | Yes |
| Mapping & Navigation | ||
| Courses | — | Yes |
| Race an activity | — | Yes |
| Power meter compatible | — | Yes |
| Compatible with Varia™ lights | — | Yes |
| Compatible with Varia headlight camera | — | Yes |
| Speed and cadence sensor support (w/sensor) | — | Yes |
| Bike lap and lap maximum power (with power sensor) | — | Yes |
| Compatible with Varia™ radar (rear-facing radar) | — | Yes |
| Compatible with Vector™ and Rally™ (power meters) | — | Yes |
| Alerts (triggers alarm when you reach goals including time, distance, heart rate or calories) | — | Yes |
| Activity Tracking Features | ||
| % HRR | — | Yes |
| % HR max | — | Yes |
| HR zones | — | Yes |
| HR alerts | — | Yes |
| Shortcuts | — | Yes |
| HRV status | — | Yes |
| Load ratio | — | Yes |
| Manual lap | — | Yes |
| Rest timer | — | Yes |
| Auto max HR | — | Yes |
| Finish time | — | Yes |
| HR calories | — | Yes |
| Voice alerts | — | Yes |
| Custom alerts | — | Yes |
| Physio TrueUp | — | Yes |
| Recovery time | — | Yes |
| Training load | — | Yes |
| VO2 Max (Run) | — | Yes |
| Course guidance | — | Yes |
| Training effect | — | Yes |
| Race an Activity | — | Yes |
| Advanced workouts | — | Yes |
| Interval training | — | Yes |
| Race glance/widget | — | Yes |
| Training load focus | — | Yes |
| VO2 Max (Trail Run) | — | Yes |
| GPS speed and distance | — | Yes |
| Configurable lap alerts | — | Yes |
| Customizable data pages | — | Yes |
| Unified training status | — | Yes |
| Touch and/or button lock | — | Yes |
| Activity history on watch | — | Yes |
| Downloadable training plans | — | Yes |
| Training effect (anaerobic) | — | Yes |
| HRM running pace and distance | — | Yes |
| Customizable activity profiles | — | Yes |
| Auto Pause® automatic timer halt | — | Yes |
| Respiration rate (during exercise) | — | yes (with compatible accessory) |
| Auto Lap® interval tracking feature | — | Yes |
| Primary benefit (Training Effect labels) | — | Yes |
| HR broadcast (broadcasts HR data over ANT+® to paired devices) | — | Yes |
| Improved interval (includes open repeats, intervals data page, rest screen and auto detection) | — | Yes |
| 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 | — | Yes |
| Compass | — | Yes |
| GLONASS | — | Yes |
| Galileo | — | Yes |
| Gyroscope | — | Yes |
| Thermometer | — | Yes |
| Accelerometer | — | Yes |
| Ambient light sensor | — | Yes |
| Barometric altimeter | — | Yes |
| Pulse Ox Blood Oxygen Saturation Monitor | — | Yes |
| Garmin Elevate™ wrist heart rate monitor | — | Yes |
| Safety and Tracking Features | ||
| TrueUp™ | — | Yes |
| Move IQ™ | — | Yes |
| Step counter | — | Yes |
| Floors climbed | — | Yes |
| Calories burned | — | Yes |
| Distance traveled | — | Yes |
| Intensity minutes | — | Yes |
| Automatic rep counting | — | Yes |
| Move Alert movement options | — | Yes |
| Garmin Connect™ Challenges app | — | yes (optional Connect IQ app) |
| Move alerts (displays on device after a period of inactivity) | — | Yes |
| Auto goal (learns your activity level and assigns a daily step goal) | — | Yes |
| Training, Planning and Analysis Features | ||
| Run workouts | — | Yes |
| Quick workout | — | Yes |
| Running power | — | Yes |
| Race predictor | — | Yes |
| Foot pod capable | — | Yes |
| Running dynamics | — | Yes |
| Grade-adjusted pace | — | Yes |
| Run/Walk/Stand detection | — | Yes |
| Stride length (real time) | — | Yes |
| PacePro™ Pacing Strategies | — | Yes |
| Vertical oscillation and ratio | — | Yes |
| Ground contact time and balance | — | yes (GCT balance with accessory) |
| GPS-based distance, time and pace | — | Yes |
| Course- and weather-specific race predictor | — | Yes |
| Cadence (provides real-time number of steps per minute) | — | Yes |
Wrist Fit
Apple Watch Ultra 3
Sits best on wrists ~52–70mm wide (≈ 13.9–18.7cm circumference).
Garmin Forerunner 170
Sits best on wrists ~45–61mm wide (≈ 12.0–16.3cm circumference).
Frequently Asked Questions
Is the Apple Watch Ultra 3 bigger than the Garmin Forerunner 170?
The Apple Watch Ultra 3 is bigger — 44mm vs 42.6mm case width.
Which fits a smaller wrist better, the Apple Watch Ultra 3 or the Garmin Forerunner 170?
The Apple Watch Ultra 3 suits wrists around 52–70mm wide, and the Garmin Forerunner 170 around 45–61mm. The one with the smaller lower bound is the safer pick for a small wrist.
Can I see the Apple Watch Ultra 3 and Garmin Forerunner 170 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.