Amazfit T-Rex 3 smartwatch review

Can you buy an outdoor watch with military-grade durability, weeks of battery life and a seemingly endless list of features, all for less than $300? Had you asked us that question a few years ago, we would probably have said no. Things are changing, though. Good quality smartwatches do not have to cost the earth these days — we know, we recently reviewed the TicWatch Atlas and were thoroughly impressed by its excellent value for money. And now another affordable gem has landed in our hands.

Designed for serious outdoor and fitness enthusiasts, the Amazfit T-Rex 3 promises up to 27 days of battery life, top-notch durability, dual-band GPS, maps, an altimeter and many other features that can come in handy when exploring the great outdoors. You can even take it diving — the Amazfit T-Rex is waterproof to 328 feet (100 meters) and can sustain free dives of up to 147 ft (44.8 m). This rugged watch also comes with over 170 sports modes, voice control, AI coaching and phone notifications.

All this, yet it costs just $279 and is frequently on sale. The Amazfit T-Rex 3 has the potential to be one of the best budget fitness trackers on the market right now.

Amazfit T-Rex 3 smartwatch review

Amazfit T-Rex 3: Design

• Durable and waterproof (including diving)
• Big, chunky and “masculine”
• Removable silicone straps

The Amazfit T-Rex 3 is made to last. It features a tough stainless steel bezel, thick silicone straps and a screen covered with scratch-resistant Gorilla glass, plus it comes with certifications that prove its extensive durability. As we mentioned before, this watch is rated 10ATM, meaning it is waterproof for up to 328 ft (100 m) and it is suitable for freediving up to 147 ft (44.8 m) thanks to its EN13319, ISO 6425 and GB/T 18828 certifications. The Amazfit T-Rex 3 can also withstand temperatures from 158 to -22 degrees Fahrenheit (70 to -30 degrees Celsius). That is impressive, because even some of the best fitness trackers do not have such top-end specs.

We tested our Amazfit T-Rex 3 for about two months and can attest to its toughness. While admittedly we did not go to extremes with the testing process (we are not professional divers), the watch did not sustain any scuffs, scratches or wear-and-tear damage. Cold February temperatures, rainwater or hot showers did not faze it either.

We also found it surprisingly comfortable to wear. The Amazfit T-Rex 3 weighs a solid 2.4 oz (68.3g) without a strap so is heavier than most of the best Garmin watches, for example, but it did not weigh our wrist down. The silicone straps were thick yet soft, and they managed to keep our watch firmly in place without aggravating the skin. We also liked that they were removable. The Amazfit T-Rex 3 comes with a strap-changing kit, and you can buy plenty of different straps online if you fancy a change.

That said, we did not really warm to the chunky design of our Amazfit T-Rex 3. The watch is just too big to be worn comfortably in bed, and unlike most mainstream models, it is only available in one size. We were not convinced by its overly rugged looks, either. While this watch would pair well with muddy boots and climbing gear, it may clash with more casual clothing. The Amazfit T-Rex 3 is somewhat impractical for 24/7 wear.

Amazfit T-Rex 3: Display

• 1.5-inch AMOLED display
• Good visibility in bright conditions
• Navigation takes some getting used to

The 1.5-inch AMOLED display definitely warrants a mention. It is pleasantly bright and colorful, and its large size makes it easy to read. The display can also be customized with hundreds of watch faces to suit your mood, style and tracking preferences. This is a major bonus point for us — we like wearables to reflect the user’s goals and personality.

More importantly, the display showed good visibility in bright or low-light conditions, even though the pictures of our T-Rex 3 may not necessarily show that (the flash produced excessive glare so we opted for natural light instead.) We also did not experience lags or any other problems with touchscreen responsiveness.

What we were slightly surprised by was its confusing navigation. It is slightly less intuitive and user-friendly than other Amazfit watches we tested, even though all of these devices share largely the same layout. However, finding different features and settings got easier the more we used the watch.

Amazfit T-Rex 3: Features

• Robust fitness-tracking features
• Dual-band GPS, altimeter and compass
• Mini apps for download from the Zepp App

The Amazfit T-Rex 3 features several sensors: An optical sensor for tracking heart rate and blood oxygen levels, an accelerometer and gyroscope sensors for assessing movement, a compass and barometric altimeter for geolocation, and finally, an ambient light sensor and body temperature sensor. The Amazfit T-Rex 3 also features dual-band GPS positioning, Wi-Fi connectivity and Bluetooth connectivity. It is a tracker in the full sense of the word.

This watch features more than 170 workout modes, personalized training plans and detailed post-workout summaries of your recovery time, training intensity and other key performance metrics. Amazfit does a good job of translating complex metrics into more digestible health advice, and T-Rex 3 is no different. It may have a more in-depth approach to fitness tracking than its less “technical” siblings Balance and Active, but it still manages to keep things relatively easy to understand. This may be particularly useful for beginners and those looking for training guidance.

The Amazfit T-Rex 3 also has a speaker and a microphone so you can answer texts from your wrist, as well as other smartwatch features. For example, it can pay for your shopping with the Zepp Pay contactless payments app, or help you with a range of day-to-day activities — a host of mini-apps is available for download from the connected Zepp app, including a Climbing difficulty calculator, Hydration advice or Pill reminder.

Last but not least, the Amazfit T-Rex 3 has plenty of features to satisfy outdoor enthusiasts, from dual-band GPS and air pressure monitoring to on-watch topographic maps and ski trails. In that regard, it easily rivals many of the premium Garmin and Apple watches.

Amazfit T-Rex 3: Performance

• Up to three weeks’ battery life
• Good GPS and fitness-tracking accuracy
• Strength-tracking features may be unreliable

According to the brand, the Amazfit T-Rex 3 lasts up to 13 days in “heavy use”, up to 27 days in “typical use” and up to 180 hours with “continuous outdoor GPS activity” — and that rings true. Our typical use would include continuous heart tracking, hour-long workouts on most days of the week and sleep tracking almost every night, and under these conditions, our watch lasted on average two to three weeks on a single charge. We did not have the opportunity to test if it lasted 180 hours with GPS on, but battery usage in that mode seemed consistent with the claim.

The tracking in the T-Rex 3 watch was largely accurate, especially with sleep, step count and certain sport-specific metrics (stroke rate in indoor rowing, for example.) GPS navigation also seemed to work well for us, locating our position with a good degree of accuracy and in a reasonable time. However, we only had the opportunity to test the watch during walks in towns and other populated areas — we can’t vouch for the accuracy of its GPS in any other environments.

The Amazfit T-Rex performed well in our heart rate test, too. We did an hour-long workout wearing both the watch and a Polar H9 chest-strap heart rate monitor, then compared the measurements between the devices. The heart rate was relatively accurate during rest and moderate activity, but it became slightly less reliable with high-intensity exercise. However, these results are consistent with the heart rate measurements given by more premium fitness trackers.

The only performance-related issue we experienced was unreliable movement tracking during strength-based workouts. The Amazfit T-Rex 3 promises to “intelligently count your reps, sets and rest time” and evaluate your movement based on stability, rhythm and other metrics. In our experience, this feature missed the mark on all accounts, with wildly inaccurate estimations and inconsistent performance during almost every resistance workout.

Amazfit T-Rex 3: User reviews

The Amazfit T-Rex 3 was rated 4.4 out of 5 stars at Amazon, with 74% of users giving it five stars. Positive reviews praised this watch for its rugged build, long battery life, large display, ease of use and value for money.

One happy user said: “I used to work for a major smartwatch company (which will remain nameless) writing manufacturing test software and running the data analytics team. […] I would have to say that this T-Rex 3 watch blows away any of the smartwatches I have seen in my previous company at a reasonable price point. It even has a more comprehensive feature set than I have seen on my Garmin Venu 2 which I use every day for my workouts.”

Mixed opinions were expressed on the looks and accuracy of sleep tracking. Negative reviews, on the other hand, tended to revolve around individual faulty units. One customer concluded: “Flimsy rubbish. Had I bought this myself I’d have returned it immediately. Watch feels like it’s out of a Lucky Bag. Avoid like the plague.”

Should you buy the Amazfit T-Rex 3?

✅ Buy it if: You want a rugged outdoor smartwatch that can give you an excellent run for your money. For less than $280, the Amazfit T-Rex 3 offers the build, functionality and performance of some of the best premium mainstream models.

❌ Do not buy it if: You want something more stylish and discreet, or if you are looking for a basic fitness tracker. This rugged watch may prove too big and chunky for comfortable sleep tracking or formal clothing, and its wide range of features may be redundant for the average gym-goer.

If the Amazfit T-Rex 3 is not for you

The TicWatch Atlas is a great alternative to the Amazfit T-Rex 3. This rugged outdoor watch boasts similar durability, features and tracking capabilities, but it looks better and costs only $70 more.

Looking for something more premium? The Garmin Fenix 8 is a perfect option here. This smartwatch is one of the best outdoor wearables on the market, and its $1,000 price tag fully reflects that.

For those looking for something smaller and simpler, we would recommend the Fitbit Inspire 3. This fitness band is stylish and comfortable to wear, and it has everything you may need for basic daily fitness tracking.

Amazfit T-Rex 3: How we tested

We spent two months testing the Amazfit T-Rex 3 smartwatch, looking at its design, features, tracking performance, connectivity with third-party devices and ease of use. We wore it during the day, while sleeping and when doing a range of workouts, from leisurely walks outdoors to high-intensity cardio and heavy weightlifting in the gym.

Finally, we assessed the accuracy of our Amazfit T-Rex 3 by comparing its heart rate measurements with the data we obtained using a Polar H9 chest-strap heart rate monitor.