GPS Running Watches / Garmin Forerunner 170 (43mm) vs Amazfit T-Rex 3 Pro (48mm)
Garmin Forerunner 170 (43mm) vs Amazfit T-Rex 3 Pro (48mm)
Amazfit T-Rex 3 Pro (48mm)
Flagship materials, maps and 38 h of dual-band GPS for $399 — with clumsy map downloads.
Wins overall by 0.8 points
Quick Verdict
The Amazfit T-Rex 3 Pro (48mm) is the stronger all-round pick, ahead by 0.8 points. Flagship materials, maps and 38 h of dual-band GPS for $399 — with clumsy map downloads.
The Garmin Forerunner 170 (43mm) and Amazfit T-Rex 3 Pro (48mm) are both closely matched GPS Running Watch models, and the Garmin Forerunner 170 (43mm) is $100 cheaper than the Amazfit T-Rex 3 Pro (48mm) ($299.99 vs $399.99). On Navigation & Maps, the Amazfit T-Rex 3 Pro (48mm) leads (7.2 vs 2.5/10) — real routable offline topographic maps versus a breadcrumb line, plus how painful it is to get maps onto the watch.. On Build & Comfort, the Garmin Forerunner 170 (43mm) leads (8.2 vs 6.4/10) — case materials, lens (sapphire vs glass), weight on the wrist and durability ratings.. On GPS Accuracy, the Amazfit T-Rex 3 Pro (48mm) leads (7.8 vs 6.2/10) — trace quality in cities and under tree cover — multiband L1+L5 hardware plus what independent testers measured in the real world.. Overall, the Amazfit T-Rex 3 Pro (48mm) scores 7.6/10 across our 8 scoring categories versus 6.8/10 for the Garmin Forerunner 170 (43mm). Below, we break down the full spec sheet, category-by-category scores, and exactly who should buy which one.
Side-by-Side Comparison
| Spec | Garmin Forerunner 170 (43mm) | Amazfit T-Rex 3 Pro (48mm) |
|---|---|---|
| Price | $299.99 | $399.99 |
| Release Year | 2026 | 2025 |
| Display | 1.2-in 390x390 AMOLED touchscreen, optional always-on | 1.5-in AMOLED, up to 3,000 nits, sapphire crystal lens, optional always-on |
| Smartwatch Battery ( days) | 10 | 25✓ |
| Always-On Display Cost | 4 days with always-on display — the headline 10-day figure assumes the screen is off between glances | Amazfit's 25-day figure is typical use; heavy use is rated 10 days and one reviewer measured about 18 days alongside 14 h of accurate GPS. Amazfit does not publish a separate always-on display figure. |
| Battery, Single-Band GPS ( h) | 20 | 85✓ |
| Battery, Multiband GPS ( h) | No multiband mode exists on this watch; all-systems (L1 only) runs 14 h | 38 |
| GNSS Bands | Single-band L1 multi-GNSS (GPS, GLONASS, Galileo, BeiDou, QZSS). No L5/dual-frequency — DC Rainmaker's hands-on and the garminrumors spec wiki both confirm this; the5krunner's spec page loosely calls it 'multi-frequency', which is wrong. Multiband starts at the Forerunner 570. | Dual-band (L1+L5) circularly-polarised GNSS. The 85 h headline is the power-saving GPS mode; the accurate dual-band mode is 37-38 h on the 48 mm and about 29 h on the 44 mm. |
| Onboard Maps | None. Breadcrumb course-following only — no TopoActive maps, no turn-by-turn, no ClimbPro. | Free offline contour maps with turn-by-turn, POI search, round-trip routing and auto-rerouting — but you must select and download each map region inside the Zepp phone app and transfer it across. Android Police called the process 'messy and time-consuming' with vague instructions. |
| Music Storage | Only on the $349.99 Forerunner 170 Music: 4 GB with offline Spotify, Amazon Music and Deezer. The $299.99 base model reviewed here has no music storage and no Wi-Fi. | Onboard storage for sideloaded MP3 files played to Bluetooth headphones. No Spotify and no streaming services. |
| Training Platform & Subscription | Garmin Connect is free and every core training metric — Training Readiness, Training Load, Training Status, HRV Status, Body Battery, recovery time — is Firstbeat-derived and free on the watch (Garmin bought Firstbeat in 2020). Connect+ is $6.99/mo or $69.99/yr and adds only AI wellness prompts, 3D maps, Trails+ routing, extra badges and nutrition logging — nothing a training plan depends on. | The Zepp app and core training/recovery metrics are free. Zepp Aura, the AI sleep and coaching layer, is a paid subscription; the training data itself is not gated behind it. |
| External Sensor Support | Pairs with both ANT+ and Bluetooth chest straps, footpods and Stryd — the cheap fix for wrist-HR interval errors | Bluetooth only — no ANT+. BLE chest straps and Stryd pods pair through Zepp OS. |
| Data Export | Full .FIT file access over USB/MTP plus free automatic sync to Strava, TrainingPeaks, Runalyze, intervals.icu and others through Garmin Connect. | Free sync to Strava, adidas Running, Apple Health and Google Health Connect, plus a TrainingPeaks Zepp OS app; .FIT export via the Zepp app |
| Warranty | 12 months | 12 months |
| Colors | Black / Amp Yellow | Black |
Category Scores
GPS Accuracy
The Amazfit T-Rex 3 Pro (48mm) leads clearly here, 7.8 against 6.2 — a 1.6-point margin on trace quality in cities and under tree cover — multiband L1+L5 hardware plus what independent testers measured in the real world.. If that is what you are buying for, the Garmin Forerunner 170 (43mm) does not close the gap elsewhere.
Battery Honesty
The Amazfit T-Rex 3 Pro (48mm) leads clearly here, 7.6 against 7.0 — a 0.6-point margin on how much of the headline battery claim survives the mode you would actually train in: all-systems plus multiband, always-on display, music playing. The number on the box is almost always the slowest, least accurate mode.. If that is what you are buying for, the Garmin Forerunner 170 (43mm) does not close the gap elsewhere.
Training & Recovery
The Garmin Forerunner 170 (43mm) leads clearly here, 7.4 against 6.8 — a 0.6-point margin on depth of load, readiness and recovery analysis, and how much of it is free rather than gated behind a subscription or an extra chest strap.. If that is what you are buying for, the Amazfit T-Rex 3 Pro (48mm) does not close the gap elsewhere.
Heart Rate
The Garmin Forerunner 170 (43mm) and Amazfit T-Rex 3 Pro (48mm) are level here, at 6.8/10 each. optical wrist accuracy during intervals and burst efforts, and whether the watch pairs with ANT+ and/or Bluetooth chest straps as a fix. is not what separates these two — look to the categories where the scores diverge.
Display
The Amazfit T-Rex 3 Pro (48mm) leads clearly here, 9.5 against 8.4 — a 1.1-point margin on brightness, resolution and daylight readability, weighing AMOLED sharpness against MIP's always-on-for-free behaviour.. If that is what you are buying for, the Garmin Forerunner 170 (43mm) does not close the gap elsewhere.
Build & Comfort
The Garmin Forerunner 170 (43mm) leads clearly here, 8.2 against 6.4 — a 1.8-point margin on case materials, lens (sapphire vs glass), weight on the wrist and durability ratings.. If that is what you are buying for, the Amazfit T-Rex 3 Pro (48mm) does not close the gap elsewhere.
Value
The Amazfit T-Rex 3 Pro (48mm) leads clearly here, 9.0 against 7.8 — a 1.2-point margin on what the watch delivers per dollar against everything else in the comparison at the moment of purchase.. If that is what you are buying for, the Garmin Forerunner 170 (43mm) does not close the gap elsewhere.
Best For
Choose the Garmin Forerunner 170 (43mm) if…
- • Build & Comfort matters most to you — the Garmin Forerunner 170 (43mm) scores 8.2/10 here (case materials, lens (sapphire vs glass), weight on the wrist and durability ratings.).
- • You want to spend less — it's $100 cheaper.
- • Your main use case is road-running or triathlon.
Choose the Amazfit T-Rex 3 Pro (48mm) if…
- • Navigation & Maps matters most to you — the Amazfit T-Rex 3 Pro (48mm) scores 7.2/10 here (real routable offline topographic maps versus a breadcrumb line, plus how painful it is to get maps onto the watch.).
- • GPS Accuracy matters most to you — the Amazfit T-Rex 3 Pro (48mm) scores 7.8/10 here (trace quality in cities and under tree cover — multiband L1+L5 hardware plus what independent testers measured in the real world.).
- • Value matters most to you — the Amazfit T-Rex 3 Pro (48mm) scores 9.0/10 here (what the watch delivers per dollar against everything else in the comparison at the moment of purchase.).
- • Display matters most to you — the Amazfit T-Rex 3 Pro (48mm) scores 9.5/10 here (brightness, resolution and daylight readability, weighing AMOLED sharpness against MIP's always-on-for-free behaviour.).
- • Your main use case is trail-ultra or hiking-navigation.
Pros & Cons
Garmin Forerunner 170 (43mm)
Pros
- +Adds a barometer, gyroscope, wrist running power, Training Readiness and open-water swimming over the Forerunner 165 it replaces
- +Every training and recovery metric is free — Connect+ at $6.99/mo adds nothing a runner's plan depends on
- +Pairs with ANT+ and Bluetooth chest straps, so $60 of strap fixes the wrist sensor for intervals
- +20 h of GPS-only battery covers a road marathon several times over
Cons
- −Single-band L1 GNSS only — in city streets or under canopy the trace drifts, and multiband costs $250 more (Forerunner 570)
- −No multisport/triathlon mode at all, so it cannot record a triathlon; DC Rainmaker flags this as the headline omission
- −No maps of any kind, and no turn-by-turn — breadcrumbs only
- −Music is a $50 upcharge: the base model has zero song storage and no Wi-Fi
- −The 10-day smartwatch claim drops to 4 days the moment you enable the always-on display
Amazfit T-Rex 3 Pro (48mm)
Pros
- +38 h of dual-band GPS and 25 days of typical use for $399.99 — Garmin charges $1,199.99 for 30 h of multiband
- +A 3,000-nit AMOLED behind sapphire with a titanium-alloy bezel at half the price of rivals with those materials
- +Free offline contour maps with genuine auto-rerouting, which even the $749.99 Forerunner 970 does not beat on price
- +10 ATM plus EN13319 freediving certification to 45 m, unusual at any price
Cons
- −Maps must be picked and downloaded region-by-region in the Zepp phone app then transferred — reviewers describe the process as messy and poorly documented
- −The 85 h battery headline is the power-saving GPS mode; the dual-band mode you would actually race on is 38 h
- −No ANT+ and no Spotify or any streaming service — sideloaded MP3 only
- −Zepp's software ecosystem and analytics are a clear step behind Garmin and COROS, and the app is cluttered
- −48 mm and chunky; reviewers found it too bulky for 24-hour wear
Shop by Need
FAQs
Is the Garmin Forerunner 170 (43mm) or Amazfit T-Rex 3 Pro (48mm) better overall?+
Based on our 8-category scoring, the Amazfit T-Rex 3 Pro (48mm) comes out ahead overall. See the full breakdown in the scores section above — the right pick still depends on which categories matter most for your use case.
Which is better for Navigation & Maps, the Garmin Forerunner 170 (43mm) or the Amazfit T-Rex 3 Pro (48mm)?+
The Amazfit T-Rex 3 Pro (48mm) scores higher on Navigation & Maps (7.2/10 vs 2.5/10) — real routable offline topographic maps versus a breadcrumb line, plus how painful it is to get maps onto the watch..
Which is better for Build & Comfort, the Garmin Forerunner 170 (43mm) or the Amazfit T-Rex 3 Pro (48mm)?+
The Garmin Forerunner 170 (43mm) scores higher on Build & Comfort (8.2/10 vs 6.4/10) — case materials, lens (sapphire vs glass), weight on the wrist and durability ratings..
Which is better for GPS Accuracy, the Garmin Forerunner 170 (43mm) or the Amazfit T-Rex 3 Pro (48mm)?+
The Amazfit T-Rex 3 Pro (48mm) scores higher on GPS Accuracy (7.8/10 vs 6.2/10) — trace quality in cities and under tree cover — multiband L1+L5 hardware plus what independent testers measured in the real world..
Which is better for Value, the Garmin Forerunner 170 (43mm) or the Amazfit T-Rex 3 Pro (48mm)?+
The Amazfit T-Rex 3 Pro (48mm) scores higher on Value (9.0/10 vs 7.8/10) — what the watch delivers per dollar against everything else in the comparison at the moment of purchase..
Is the Garmin Forerunner 170 (43mm) worth the price difference over the Amazfit T-Rex 3 Pro (48mm)?+
The Garmin Forerunner 170 (43mm) is the cheaper option at $299.99 versus $399.99. Whether the pricier model is "worth it" depends on how much you value its lead in Navigation & Maps.
Which is better suited to my use case?+
The Garmin Forerunner 170 (43mm) is the better fit if you mainly care about road-running or triathlon. The Amazfit T-Rex 3 Pro (48mm) is the better fit for trail-ultra or hiking-navigation.
What's the warranty on the Garmin Forerunner 170 (43mm) vs the Amazfit T-Rex 3 Pro (48mm)?+
The Garmin Forerunner 170 (43mm) ships with a 12-month warranty; the Amazfit T-Rex 3 Pro (48mm) ships with a 12-month warranty. Always confirm current terms on the manufacturer's site before buying.
Should I wait for the next model instead of buying either of these?+
If either model is more than two years old, a successor may be close — check the "Latest Model" link on each product page. Otherwise, both are current, well-supported options and there's no strong reason to wait.
Cheaper Option
COROS PACE 4 (silicone band) — $249.00
Premium Option
COROS APEX 4 (42mm) — $429.00
Specifications and prices for both products last verified . Scores are calculated from published specifications — see how we compare products.