Amazfit Active 3 Premium vs Amazfit T-Rex 3: which should you buy?

Get the Amazfit Active 3 Premium. It is the better watch for running, heart rate and sleep, and it is far lighter to wear: Amazfit lists 38g against 68.3g without the strap. The Amazfit T-Rex 3 is a rugged outdoor watch, and you pay for that in weight on your wrist.

Who should get the Amazfit Active 3 Premium

Get the Active 3 Premium if you want a light everyday watch that takes running seriously. Amazfit gives it built-in running workouts, coached plans from a 5K to a marathon, and running power, plus heart rate, blood oxygen, skin temperature and sleep tracking with no subscription. It also carries free offline maps with turn-by-turn directions. On an iPhone it works with limits, so some features that need deeper phone access stay on Android.

Who should get the Amazfit T-Rex 3

Get the T-Rex 3 if you head into rough country. Amazfit builds it to a military-grade standard and rates it for up to 42 hours in accurate GPS mode, which covers long hikes with room to spare. It works with an iPhone and with an Android phone, and it shrugs off rocks, mud and cold.

The differences that matter

The Active 3 Premium has the brighter screen too, at up to 3,000 nits against 2,000 nits. On a sunny run you will see the difference.

The T-Rex 3 is the tougher of the two, rated 10 ATM against 5 ATM and built to military standards. If you climb, dive or camp, that is real value.

Price and value

Today the Amazfit Active 3 Premium costs $169.99 (checked Nov. 4, 2026) and the Amazfit T-Rex 3 costs $244.99 (checked Nov. 4, 2026). The Amazfit Active 3 Premium is cheaper by $75.

For everyday training, the lighter watch wins. Pick the Amazfit Active 3 Premium.