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Amazfit T-Rex 3 Pro
Spend $399.99 on Amazfit T-Rex 3 Pro for a rugged watch with sapphire, a titanium bezel and a 3,000-nit screen, in 44mm or 48mm.
In short
Spend $399.99 on Amazfit T-Rex 3 Pro for a rugged watch with sapphire, a titanium bezel and a 3,000-nit screen, in 44mm or 48mm. The 48mm is rated for 25 days of typical use and 38 hours of accurate GPS; the 44mm manages 17 days and 26 hours. The $279 T-Rex 3 is rated to last longer, about 27 days, but it's 48mm only, dimmer, and has no published GPS ratings.
Product images
Amazfit T-Rex 3 Pro, from its Amazon listing.
Credit: Amazon.com (Associates Program). Amazon listing
Product image from the Amazon listing.
Who it is for
- Hikers and mountaineers who plan by the numbers. The 48mm is rated for up to 85 hours in GPS Long Battery Life mode and 116 in GPS Max Battery Life, with barometric storm alerts and high-altitude alerts.
- Smaller wrists that still want a rugged watch. The 44mm weighs 46.8 grams without the strap and fits 140–205mm wrists.
- T-Rex 3 owners who want the better finish: sapphire, a Grade 5 titanium bezel and buttons, and a 3,000-nit screen.
Who should skip it
- Anyone who mainly wants battery life for less. The $279.99 T-Rex 3 gets about 27 days from a charge in typical use, and Amazfit gives it 4GB for maps.
- Anyone who doesn't need a rugged watch. Balance 3 costs about the same and comes in titanium or steel.
What sets it apart
- Sapphire over a 3,000-nit AMOLED; T-Rex 3 is rated at 2,000 nits.
- A Grade 5 titanium bezel and buttons on a fiber-reinforced polymer case.
- Two sizes: 48mm with a 1.5-inch, 480 × 480 screen, or 44mm with a 1.32-inch, 466 × 466 screen.
- Published GPS ratings: 38 hours in Accurate mode on the 48mm (26 on the 44mm), and up to 116 hours (86) in GPS Max Battery Life mode.
- A flashlight with Boost Mode, Bluetooth calls, 2.4GHz Wi-Fi and Zepp OS 5.
Caveats
- On the 44mm, the $399 Pro gives up roughly a third of the 48mm's battery in most modes: 17 days of typical use instead of 25, and 26 hours of accurate GPS instead of 38.
- Two numbers are missing for the Pro: its storage, and a time-to-80% charging figure.
Key specs
In the same order on every watch page, so you can compare models.
| Spec | Value | Source and notes |
|---|---|---|
| Display size | 48mm: 1.5-inch AMOLED; 44mm: 1.32-inch AMOLED | Amazfit T-Rex 3 Pro specs |
| Display type | AMOLED under sapphire glass | Amazfit T-Rex 3 Pro specs |
| Display resolution | 48mm: 480 × 480 (322 ppi); 44mm: 466 × 466 (353 ppi) | Amazfit T-Rex 3 Pro specs |
| Peak brightness | Up to 3,000 nits | Amazfit T-Rex 3 Pro specsT-Rex 3 peaks at 2,000 nits. |
| Case size(s) | 48mm and 44mm | Amazfit T-Rex 3 Pro specs |
| Case material | Fiber-reinforced polymer case; Grade 5 titanium bezel and 4 buttons | Amazfit T-Rex 3 Pro specs |
| Case dimensions | 48mm: 48 × 48 × 14mm; 44mm: 44.8 × 44.8 × 13.2mm | Amazfit T-Rex 3 Pro specsAmazfit's own comparison lists T-Rex 3 at 48.5 × 48.5 × 13.75mm. |
| Weight | Without strap: 48mm 52 g; 44mm 46.8 g | Amazfit T-Rex 3 Pro specs |
| Finishes | 48mm: Tactical Black, Black Gold. 44mm: Tactical Black, Black Gold, Arctic Gold (all $399.99 on Amazfit's US store) | Amazfit T-Rex 3 Pro product page |
| Battery, typical use | Typical use: up to 25 days (48mm), 17 days (44mm). Heavy use: up to 10 days, 8 days. Batteries: 700 mAh, 500 mAh | Amazfit T-Rex 3 Pro specs |
| Battery, saver mode | Low Temperature Mode, GPS off: up to 25 days (48mm), 14 days (44mm). GPS Max Battery Life: up to 116 hours, 86 hours | Amazfit T-Rex 3 Pro specs |
| Battery, GPS | Accurate GPS: up to 38 hours (48mm), 26 hours (44mm). Power-Saving GPS: 74, 51 hours. GPS Long Battery Life: 85, 60 hours. Low Temperature Mode with GPS on: 25, 14 hours | Amazfit T-Rex 3 Pro specs |
| Charging | Magnetic charging head (no cable listed); Amazfit gives no time to 80% | Amazfit T-Rex 3 Pro specs |
| Water resistance | 10 ATM; Amazfit's comparison adds freediving and scuba to 45m | Amazfit T-Rex 3 Pro specs and comparison |
| GNSS / GPS | Dual-band and single-band; six satellite systems; Accuracy, Automatic and Power Saving modes; circularly polarized antenna | Amazfit T-Rex 3 Pro specs |
| Cellular | No cellular model; Bluetooth calls through the built-in mic and speaker | Amazfit T-Rex 3 Pro specs |
| Heart rate | BioTracker 6.0 PPG (5PD + 2LED); 24-hour heart rate; high and low alerts | Amazfit T-Rex 3 Pro specs |
| Blood oxygen (SpO2) | 24-hour blood-oxygen monitoring plus manual readings | Amazfit T-Rex 3 Pro specs |
| Temperature sensing | Temperature sensor; 24-hour skin temperature | Amazfit T-Rex 3 Pro specs |
| Sleep tracking | Sleep stages including REM; naps; sleep schedule; breathing quality; sleep score; sleep HRV | Amazfit T-Rex 3 Pro specs |
| Workout types | 187 sports modes; automatic recognition of strength and sports movements; Track Run; virtual pacer; HYROX; Zepp Coach | Amazfit T-Rex 3 Pro specs |
| Other sensors | Accelerometer; gyroscope; geomagnetic; barometric altimeter; ambient light; temperature | Amazfit T-Rex 3 Pro specs |
| Durability / ingress | 10 ATM; MIL-STD-810H-2019 per Amazfit (report H202505284651-01EN for the 48mm, H202509017818-01EN for the 44mm); prolonged exposure not recommended | Amazfit T-Rex 3 Pro footnotes |
| Safety / incident alerts | High and low heart-rate, low blood-oxygen and high-stress alerts; blood-oxygen prompts at altitude; barometric storm alert; high-altitude alert; no Crash Detection listed | Amazfit T-Rex 3 Pro specs |
| Operating system | Zepp OS 5 (T-Rex 3 runs Zepp OS 4.5) | Amazfit T-Rex 3 Pro FAQ and comparison |
| Phone compatibility | Android 7.0 or later; iOS 15.0 or later; Zepp app | Amazfit T-Rex 3 Pro specs |
| Wireless (Wi-Fi / Bluetooth) | Wi-Fi 2.4GHz; Bluetooth 5.2 and BLE; calls through the built-in mic and speaker | Amazfit T-Rex 3 Pro specs |
| Band / strap system | Silicone strap: 22mm on the 48mm (fits 145–210mm wrists), 20mm on the 44mm (140–205mm); classic pin buckle | Amazfit T-Rex 3 Pro specs |
| US price | $399.99 on Amazfit's US store (19 September 2026) | Amazfit US store |
| Price band | Rugged midrange ($350–$450) | Based on the $399.99 US price |
| Availability | On sale at Amazfit's US store for $399.99 on 19 September 2026; the 48mm in Black Gold was sold out that day | Amazfit US store |
Amazfit T-Rex 3 Pro extras
Specs only this model has.
| Spec | Value | Source and notes |
|---|---|---|
| Sizes against T-Rex 3 | T-Rex 3 Pro: 44mm and 48mm. T-Rex 3: 48mm only | Amazfit US product pages for both watches |
| Flashlight | Flashlight with Boost Mode | Amazfit T-Rex 3 Pro product page |
| Dive features | 10 ATM; freediving and scuba to 45m in Amazfit's comparison; Auto Dive Detection | Amazfit T-Rex 3 Pro product page |
| Zepp OS | Zepp OS 5; T-Rex 3 runs Zepp OS 4.5 | Amazfit T-Rex 3 Pro FAQ |
| Against T-Rex 3 | This watch first, T-Rex 3 second. Price: $399.99 vs $279.99. Sizes: 44mm or 48mm vs 48mm only. Brightness: 3,000 vs 2,000 nits. Typical battery: 25 days (48mm) or 17 (44mm) vs about 27; T-Rex 3 also claims 40 days in battery saver. GPS ratings: published vs none. Software: Zepp OS 5 vs 4.5. This watch adds sapphire and a Grade 5 titanium bezel | Amazfit US product pages for both watches |
What the Pro adds over T-Rex 3
T-Rex 3 Pro is $399.99, against $279.99 for T-Rex 3. The extra buys better materials and harder numbers: sapphire over a brighter 3,000-nit screen, a Grade 5 titanium bezel and buttons, a 44mm size alongside the 48mm, the newer Zepp OS 5, and GPS battery ratings, which T-Rex 3 comes without. Amazfit also lists a flashlight with Boost Mode and Bluetooth calling for the Pro, neither of which appears in T-Rex 3’s specs.
T-Rex 3 holds its own on battery and storage. Its typical-use rating, about 27 days, beats the 48mm Pro’s 25, and Amazfit lists 4GB for its offline maps, where the Pro’s storage isn’t stated. The two 48mm cases are close in size. Amazfit’s comparison puts T-Rex 3 at 48.5 × 48.5 × 13.75mm and the Pro at 48 × 48 × 14mm.
If you don’t need a rugged watch at all, Balance 3 is Amazfit’s dressier choice at around $400.
Battery and GPS ratings
| Mode | 48mm | 44mm |
|---|---|---|
| Typical use | Up to 25 days | Up to 17 days |
| Heavy use | Up to 10 days | Up to 8 days |
| Accurate GPS | Up to 38 hours | Up to 26 hours |
| Power-Saving GPS | Up to 74 hours | Up to 51 hours |
| GPS Long Battery Life | Up to 85 hours | Up to 60 hours |
| GPS Max Battery Life | Up to 116 hours | Up to 86 hours |
| Low Temperature Mode, GPS off | Up to 25 days | Up to 14 days |
| Low Temperature Mode, GPS on | Up to 25 hours | Up to 14 hours |
| Battery | 700 mAh | 500 mAh |
GPS Max Battery Life stretches the 48mm to 116 hours, nearly five days of tracking, which is the number to look at for a multi-day trek. A magnetic charging head comes in the box.
Toughness, water and altitude
Amazfit tested both sizes to MIL-STD-810H-2019, though its own fine print says not to leave the watch in those conditions for long. The Pro is rated 10 ATM, with Auto Dive Detection built in. For the mountains, it adds blood-oxygen prompts at altitude, barometric storm alerts and high-altitude alerts, with a barometric altimeter behind them.
Software, phones and tracking
The Pro runs Zepp OS 5, a step up from T-Rex 3’s 4.5, and works with Android 7 or iOS 15 and later through the Zepp app. The sports list runs past 180 modes (187, to be exact), with automatic recognition of strength and sports movements, Track Run, a virtual pacer, HYROX and Zepp Coach. BioTracker 6.0 tracks heart rate, SpO2 and skin temperature around the clock, and sleep tracking covers HRV and breathing quality as well as stages and naps.
Price
Amazfit priced both sizes at $399.99 in the US on 19 September 2026, though the 48mm in Black Gold was sold out that day. It sits just under $400; check that the size and color you want is in stock before you order.
Sources
- Amazon product listing — accessed 2026-09-20
- Amazfit US — T-Rex 3 Pro product page and specs — accessed 2026-09-19
Frequently asked questions
44mm or 48mm: which T-Rex 3 Pro should I get?
The 48mm, if battery matters most: 25 days of typical use and 38 hours of accurate GPS, against 17 days and 26 hours. The 44mm suits smaller wrists, fitting 140–205mm on its 20mm strap (the 48mm's 22mm strap fits 145–210mm), weighs 46.8 grams to the 48mm's 52 without the strap, and adds an Arctic Gold finish.
Does T-Rex 3 Pro detect dives automatically?
Yes. Amazfit lists Auto Dive Detection, and its comparison rates the Pro for freediving and scuba to 45 meters, on top of 10 ATM.
What battery life does T-Rex 3 Pro get in the cold?
Amazfit's Low Temperature Mode is rated for up to 25 days with GPS off on the 48mm, or 14 days on the 44mm. With GPS on in that mode, the ratings are 25 and 14 hours.
Does T-Rex 3 Pro run newer software than T-Rex 3?
Yes. It runs Zepp OS 5, where T-Rex 3 runs Zepp OS 4.5.
Official product page: Amazfit T-Rex 3 Pro. Tech specs: Amazfit T-Rex 3 Pro specs.