Garmin
Forerunner® 165 vs Instinct® 3 – 45 mm, Solar
Size, specs & wrist fit compared
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Which one fits you
On wrists narrower than about 47mm, the Forerunner® 165 is the safer pick — it stays proportionate down to roughly 45mm, where the Instinct® 3 – 45 mm, Solar starts to hang over the edge. Above 47mm both sit cleanly, and the Instinct® 3 – 45 mm, Solar gives you more presence.
The Instinct® 3 – 45 mm, Solar wears larger than the Forerunner® 165 (45mm vs 43mm case), giving it more wrist presence — and needing a wider wrist to sit cleanly.
The Forerunner® 165 is the slimmer of the two (11.6mm vs 14.9mm), so it slides under a cuff more easily.
On the wrist the Forerunner® 165 feels lighter (39g vs 52g, case only).
Among the 318 43mm watches we hold thickness for, the Forerunner® 165 is thinner than 86%, so it wears flatter than its width suggests.
Among the 385 45mm watches we hold thickness for, the Instinct® 3 – 45 mm, Solar is thicker than 84% — it will sit high even though the case width reads modest.
The Instinct® 3 – 45 mm, Solar is 2mm wider, 2mm longer, 3.3mm thicker and 13g heavier than the Forerunner® 165. Both are circular.
Forerunner® 165
Instinct® 3 – 45 mm, Solar
Switch or add watches
Garmin
Forerunner® 165
Garmin
Instinct® 3 – 45 mm, Solar
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.
Measure at the point where you wear your watch — typically just below the wrist bone.
Flat width — lay your arm on a table, palm facing up, and measure straight across the top of your wrist with a ruler. Bone to bone; do not follow the curve down the sides.
Around — wrap a tape measure snugly round the wrist. No tape? Wrap a strip of paper, mark the overlap and hold the strip against a ruler.
Width ≠ circumference. They are different numbers — around 170mm is about 64mm across — so set the toggle to whichever one you actually measured before you type it in.
Garmin Forerunner® 165
Case 43.0mm · Lug-to-lug 43.0mm · Thickness 11.6mm · 39g
Balanced Fit
43mm 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 43mm, so you could go bigger.
Measure where you wear it, just below the wrist bone. Either of these works — the tool converts between them.
- 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. Around — a tape, or a strip of paper marked and held against a ruler, snug the whole way round.
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 measurementsHide the measurements
- Across the wrist6.0mm spare each side
Comfortable, with visible skin either side.
- Off the wrist11.6mm off the skin
Normal sports-watch height for a wrist this size. (11.6mm 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 wrist39g
Light enough to forget you have it on. (0.7g per mm of wrist)
Garmin Instinct® 3 – 45 mm, Solar
Case 45.0mm · Lug-to-lug 45.0mm · Thickness 14.9mm · 52g
Balanced Fit
45mm on a 55mm wrist
Across the wrist it works — 5.0mm 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 45mm, so you could go bigger.
Measure where you wear it, just below the wrist bone. Either of these works — the tool converts between them.
- 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. Around — a tape, or a strip of paper marked and held against a ruler, snug the whole way round.
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 measurementsHide the measurements
- Across the wrist5.0mm spare each side
Comfortable, with visible skin either side.
- Off the wrist14.9mm off the skin
A tall watch on this wrist. Fine over a sleeve, awkward under one. (14.9mm case, back against the skin)
- How it seats~5.2mm under the rim
Seats well, with the case back following most of the wrist.
- Weight on the wrist52g
Light enough to forget you have it on. (0.9g 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® 16543mm · 11.6mm thick
- Garmin Instinct® 3 – 45 mm, Solar45mm · 14.9mm thick
3D preview
Forerunner® 165 vs Instinct® 3 – 45 mm, Solar 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 Instinct® 3 – 45 mm, Solar lasts 2.5× as long as the Forerunner® 165 (28 days against 11 days).
Forerunner® 165Instinct® 3 – 45 mm, Solar
Battery Saver
—65 daysExpedition GPS
—36 daysSmartwatch
11 days28 daysBattery Saver Smartwatch
20 days—Max Battery GPS
—100 hoursGPS Only
—40 hours +130 hoursAll Satellite Systems
—28 hours +50 hoursAll Satellite Systems + Multi-Band
—24 hours +40 hoursGPS-Only GNSS
19 hours—All-Systems GNSS
17 hours—
Amber figures are the solar-assisted runtime the manufacturer publishes for that mode.
Specifications
The short version
7 key specs| Spec | GarminForerunner® 165 | GarminInstinct® 3 – 45 mm, Solar |
|---|---|---|
| Case Width | 43mm | 45mm |
| Thickness | 11.6mm | 14.9mm |
| Weight | 39g | 52g |
| Shape | Circular | Circular |
| Display type | AMOLED (optional always-on mode) | Monochrome, sunlight-visible, transflective memory-in-pixel (MIP) |
| Battery life | Smartwatch mode: Up to 11 days Battery Saver Smartwatch mode: Up to 20 days GPS-Only GNSS mode: Up to 19 hours All-Systems GNSS mode: Up to 17 hours See Details | Smartwatch: Up to 28 days/Unlimited with solar* Battery Saver Watch Mode: Up to 65 days/Unlimited with solar* GPS Only: Up to 40 hours/130 hours with solar** All Satellite Systems: Up to 28 hours/50 hours with solar** All Satellite Systems + Multi-Band: Up to 24 hours/40 hours with solar*** Max Battery GPS: Up to 100 hours/Unlimited with solar** Expedition GPS: Up to 36 days/Unlimited with solar* *Solar charging, assuming all-day wear with 3 hours per day outside in 50,000 lux conditions **Solar charging, assuming use in 50,000 lux conditions ***Solar charging, assuming use in 50,000 lux conditions; assuming typical use with SatIQ technology |
| Released | 2024 | 2025 |
Every specification
264 specs| Spec | Garmin Forerunner® 165 | Garmin Instinct® 3 – 45 mm, Solar |
|---|---|---|
| Overview | ||
| Family | Garmin | Garmin |
| General | ||
| Battery life | Smartwatch mode: Up to 11 days Battery Saver Smartwatch mode: Up to 20 days GPS-Only GNSS mode: Up to 19 hours All-Systems GNSS mode: Up to 17 hours See Details | Smartwatch: Up to 28 days/Unlimited with solar* Battery Saver Watch Mode: Up to 65 days/Unlimited with solar* GPS Only: Up to 40 hours/130 hours with solar** All Satellite Systems: Up to 28 hours/50 hours with solar** All Satellite Systems + Multi-Band: Up to 24 hours/40 hours with solar*** Max Battery GPS: Up to 100 hours/Unlimited with solar** Expedition GPS: Up to 36 days/Unlimited with solar* *Solar charging, assuming all-day wear with 3 hours per day outside in 50,000 lux conditions **Solar charging, assuming use in 50,000 lux conditions ***Solar charging, assuming use in 50,000 lux conditions; assuming typical use with SatIQ technology |
| Battery type | Lithium ion | Lithium ion |
| Display Size | 1.2" (30.4 mm) diameter | custom, two-window design; 0.9” x 0.9” (23 x 23 mm) |
| Color display | Yes | — |
| Lens Material | chemically strengthened glass | Power Glass™ |
| Bezel Material | fiber-reinforced polymer | fiber-reinforced polymer/aluminum |
| Memory/History | 4 GB | 128 MB |
| Strap material | silicone | silicone |
| Charging method | Garmin proprietary plug charger | Garmin proprietary plug charger |
| Large font option | Yes | — |
| Display resolution | 390 x 390 pixels | 176 x 176 pixels |
| Quick Release bands | yes (20 mm, Industry standard) | — |
| Case material | — | fiber-reinforced polymer |
| QuickFit® watch band compatible | — | yes (22 mm) |
| Sensors | ||
| GPS | Yes | Yes |
| Compass | Yes | Yes |
| GLONASS | Yes | Yes |
| Galileo | Yes | Yes |
| Thermometer | Yes | Yes |
| Accelerometer | Yes | Yes |
| Ambient light sensor | Yes | — |
| Barometric altimeter | Yes | Yes |
| Pulse Ox Blood Oxygen Saturation Monitor | Yes | Yes |
| Garmin Elevate™ wrist heart rate monitor | Yes | Yes |
| Gyroscope | — | Yes |
| SatIQ™ Technology | — | Yes |
| Product Info | ||
| Main SKU | 010-02863-20 | 010-02934-00 |
| Product ID | 1055469 | 1315317 |
| Product Name | Forerunner® 165 | Instinct® 3 – 45 mm, Solar |
| Release Date | 2/20/2024 | 1/6/2025 |
| Product Variation | Black/Slate Gray | Black with Black Band |
| Clock Features | ||
| Timer | Yes | Yes |
| Stopwatch | Yes | Yes |
| Time/date | Yes | Yes |
| Alarm clock | Yes | Yes |
| GPS Time Sync | Yes | Yes |
| Sunrise/sunset times | Yes | Yes |
| Automatic daylight saving time | Yes | Yes |
| Cycling Features | ||
| Courses | Yes | Yes |
| Compatible with Varia™ lights | Yes | Yes |
| Compatible with Varia headlight camera | Yes | — |
| Speed and cadence sensor support (w/sensor) | Yes | Yes |
| Compatible with Varia™ radar (rear-facing radar) | Yes | Yes |
| Alerts (triggers alarm when you reach goals including time, distance, heart rate or calories) | Yes | Yes |
| MTB Grit & Flow | — | Yes |
| Race an activity | — | Yes |
| Power meter compatible | — | Yes |
| Advanced cycling dynamics | — | Yes |
| FTP (Functional Threshold Power) | — | Yes |
| Bike lap and lap maximum power (with power sensor) | — | Yes |
| Compatible with Vector™ and Rally™ (power meters) | — | Yes |
| Compatible with Varia Vision™ (head-mounted display) | — | Yes |
| Running Features | ||
| Run workouts | Yes | Yes |
| Running power | Yes | Yes |
| Race predictor | Yes | Yes |
| Foot pod capable | Yes | Yes |
| Running dynamics | Yes | 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 (but not balance) | yes (GCT balance with accessory) |
| GPS-based distance, time and pace | Yes | Yes |
| Course- and weather-specific race predictor | Yes | — |
| Cadence (provides real-time number of steps per minute) | Yes | Yes |
| Lactate threshold | — | yes (with compatible accessory) |
| Grade-adjusted pace | — | Yes |
| Trail run auto climb | — | Yes |
| Performance condition | — | Yes |
| What You'll Love | ||
| Touchscreen | Yes | — |
| Display type | AMOLED (optional always-on mode) | Monochrome, sunlight-visible, transflective memory-in-pixel (MIP) |
| Water rating | 5 ATM | 10 ATM |
| Garmin Pay™ | Yes | Yes |
| Pulse Ox blood oxygen | yes (spot-check, during sleep, all day) | Yes |
| Sleep score and insights | Yes | Yes |
| Battery life (smartwatch mode) | Up to 11 days | Up to 28 daysUnlimited with solar |
| LED flashlight | — | Yes |
| Multi-band GPS | — | Yes |
| Solar Charging | — | Yes |
| Training status | — | Yes |
| Training readiness | — | Yes |
| Activity Profiles | ||
| Gym | Strength, HIIT, Cardio, Elliptical Training, Stair Stepping, Floor Climbing | Strength, HIIT, Cardio, Elliptical Training, Stair Stepping, Floor Climbing, Indoor Rowing |
| Swim | Pool Swimming, Open Water Swimming | Pool Swimming, Open Water Swimming |
| Cycling | Biking, Indoor Biking | Biking, Road Biking, Mountain Biking, Gravel Biking, Bike Commuting, Bike Touring, eBiking, eMountain Biking, Indoor Biking, Cyclocross, BMX |
| Wellness | Walking, Pilates, Yoga, Indoor Walking | Walking, Indoor Walking, Pilates, Yoga |
| Racket sports | Tennis, Pickleball, Padel | 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 | Running, Outdoor Track Running, Trail Running, Obstacle Racing |
| Outdoor recreation | Hiking | Hiking, Rucking, Indoor Climbing, Bouldering, Climbing, Hunting, Horseback Riding, Golfing, Disc Golf, Archery |
| Multisport | — | Triathlon |
| 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, Surfing, Kiteboarding, Windsurfing, Fishing, Boating, Water Skiing, Snorkeling, Wakeboarding, Wakesurfing, Tubing, Whitewater |
| Snow & winter | — | Skiing, Snowboarding, Backcountry Snowboarding, XC Classic Skiing, XC Skate Skiing, Backcountry Skiing, Ice Skating, Snowshoeing |
| Other activity profiles | — | Tactical, Inline Skating |
| Swimming Features | ||
| 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 | Yes |
| Pool swim workouts | — | Yes |
| Heart rate from external HRM (real-time during rests, interval and session stats during rests, and automatic heart rate download post-swim) | — | Yes |
| Outdoor Recreation | ||
| Auto rest | Yes | — |
| TracBack® | Yes | Yes |
| Back to start | Yes | Yes |
| Fish forecast | yes (via Connect IQ™) | — |
| UltraTrac mode | Yes | Yes |
| Area calculation | yes (via Connect IQ™) | Yes |
| Elevation profile | Yes | Yes |
| Total ascent/descent | Yes | Yes |
| Future elevation plot | Yes | Yes |
| Distance to destination | Yes | Yes |
| Sun and moon information | yes (via Connect IQ™) | Yes |
| Point-to-point navigation | Yes | Yes |
| Rest Timer (Ultra Run only) | Yes | — |
| Bread crumb trail in real time | Yes | Yes |
| Tides | — | Yes |
| Sight 'N Go | — | Yes |
| Tide glance | — | Yes |
| Vertical speed | — | Yes |
| GPS coordinates | — | Yes |
| Reference point | — | Yes |
| Projected waypoint | — | Yes |
| Expedition GPS Activity | — | Yes |
| Barometric trend indicator with Storm Alert | — | Yes |
| Daily Smart Features | ||
| Calendar | Yes | Yes |
| Passcode | Yes | Yes |
| Connectivity | Bluetooth®, ANT+® | Bluetooth®, ANT+® |
| Garmin Share | Yes | Yes |
| Find My Phone | Yes | Yes |
| Find My Watch | Yes | Yes |
| Morning report | Yes | Yes |
| Red shift mode | Yes | — |
| Weather forecasts | Yes | Yes |
| Smart Notifications | Yes | 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 | — |
| Pairs with Garmin Connect™ Mobile | Yes | Yes |
| Compatible with Garmin Messenger app | 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 | — |
| Text response/reject phone call with text (Android™ only) | Yes | Yes |
| Connect IQ™ (downloadable watch faces, data fields and apps) | Yes | Yes |
| VIRB® Remote | — | Yes |
| Smart trainer control | — | Yes |
| Activity Tracking Features | ||
| TrueUp™ | Yes | Yes |
| Move IQ™ | Yes | Yes |
| Step counter | Yes | Yes |
| Floors climbed | Yes | Yes |
| Calories burned | Yes | Yes |
| Distance traveled | Yes | Yes |
| Intensity minutes | Yes | Yes |
| Automatic rep counting | 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 |
| Workout and Training Plans | ||
| HIIT workouts | Yes | Yes |
| Yoga workouts | Yes | Yes |
| Cardio workouts | Yes | Yes |
| Pilates workouts | Yes | Yes |
| Strength workouts | Yes | Yes |
| Garmin Running Coach | yes (no strength add-on) | — |
| Garmin Running Coach Experts | Yes | Yes |
| Garmin Coach - Prebuilt Cycling Plans | Yes | Yes |
| Daily Suggested Workout - Running (Pace and Heart Rate Based) | Yes | Yes |
| Daily Suggested Workout - Cycling (Pace and Heart Rate Based) | — | Yes |
| Health & Wellness Monitoring | ||
| 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 |
| 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 |
| 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 |
| Wrist-based heart rate (constant, every second) | Yes | Yes |
| Sleep coach | — | Yes |
| Safety and Tracking Features | ||
| Assistance | Yes | Yes |
| Live Event Sharing | Android™ Only | Yes |
| Incident Detection during select activities | Yes | Yes |
| Incident detection alert on phone for wearables | Yes | Yes |
| Kid Activity Tracking Features | ||
| Toe-to-Toe™ Challenges app | yes (optional Connect IQ Toe-to-Toe™ Challenges app) | yes (optional Connect IQ Toe-to-Toe™ Challenges app) |
| Training, Planning and Analysis Features | ||
| % HRR | Yes | Yes |
| % HR max | Yes | Yes |
| HR zones | Yes | Yes |
| HR alerts | Yes | Yes |
| HRV status | 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 |
| Physio TrueUp | Yes | Yes |
| Recovery time | Yes | Yes |
| VO2 Max (Run) | Yes | Yes |
| Course guidance | Yes | Yes |
| Training effect | Yes | Yes |
| Advanced workouts | Yes | Yes |
| Interval training | Yes | Yes |
| Race glance/widget | Yes | Yes |
| VO2 Max (Trail Run) | Yes | Yes |
| GPS speed and distance | Yes | Yes |
| Configurable lap alerts | Yes | Yes |
| Customizable data pages | 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) | Yoga and Breathwork only | 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 |
| Shortcuts | — | Yes |
| Load ratio | — | Yes |
| Auto scroll | — | Yes |
| Custom alerts | — | Yes |
| Training load | — | Yes |
| Virtual Partner | — | Yes |
| Workout benefit | — | Yes |
| Race an Activity | — | Yes |
| Training load focus | — | Yes |
| Unified training status | — | Yes |
| Multisport auto transition | — | Yes |
| Manual multisport activities | — | Yes |
| Heat and altitude acclimation | — | Yes |
| Power Modes - customizable in-activity battery settings | — | Yes |
| Improved interval (includes open repeats, intervals data page, rest screen and auto detection) | — | Yes |
| Gaming Features | ||
| Gaming Activity | — | Yes |
| GameOn™ app compatible | — | Yes |
| Golfing Features | ||
| Tournament legal | — | Yes |
| Digital scorecard | — | Yes |
| Garmin AutoShot™ | — | Yes |
| Round timer/odometer | — | Yes |
| Auto CourseView updates | — | Yes |
| Yardage to layups/doglegs | — | Yes |
| Hazards and course targets | — | Yes |
| Pairs with Garmin Golf app | — | Yes |
| Green View with manual pin position | — | 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 |
| Measures shot distance (calculates exact yardage for shots from anywhere on course) | — | manual |
| Tactical Features | ||
| XERO™ Locations | — | Yes |
| Dual grid coordinates | — | Yes |
Wrist Fit
Garmin Forerunner® 165
Sits best on wrists ~45–61mm wide (≈ 12.0–16.3cm circumference).
Garmin Instinct® 3 – 45 mm, Solar
Sits best on wrists ~47–64mm wide (≈ 12.6–17.1cm circumference).
Frequently Asked Questions
Is the Garmin Forerunner® 165 bigger than the Garmin Instinct® 3 – 45 mm, Solar?
The Garmin Instinct® 3 – 45 mm, Solar is bigger — 45mm vs 43mm case width.
Which fits a smaller wrist better, the Garmin Forerunner® 165 or the Garmin Instinct® 3 – 45 mm, Solar?
The Garmin Forerunner® 165 suits wrists around 45–61mm wide, and the Garmin Instinct® 3 – 45 mm, Solar around 47–64mm. The one with the smaller lower bound is the safer pick for a small wrist.
Can I see the Garmin Forerunner® 165 and Garmin Instinct® 3 – 45 mm, Solar 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.

