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Amazfit T-Rex 3 vs Garmin Venu 4 (45 mm)

The specs that matter for triathlon, side by side, from each maker’s own published figures.

Specs for Amazfit T-Rex 3 and Garmin Venu 4 (45 mm)
SpecAmazfit T-Rex 3Garmin Venu 4 (45 mm)
GPS battery 42 h 20 h
Smartwatch battery 27 days 12 days
Triathlon / multisport mode Yes Yes
Onboard maps Yes No
Open-water GPS (our rating) 5 / 5 4 / 5
Weight 68.3 g 56 g
Screen AMOLED AMOLED 454x454
Price See retailer ~$549.99

Open-water GPS is our 1–5 rating from the satellite systems each maker lists: multi-band receivers score 5. Everything else is the maker’s own figure.

Which should you pick?

Amazfit

Pick the T-Rex 3 if…

  • you want the longer GPS battery: 42 h vs 20 h
  • you want the longer smartwatch battery: 27 days vs 12 days
  • you want onboard maps
  • you want better open-water GPS (our rating): 5 / 5 vs 4 / 5
Check price →
Garmin

Pick the Venu 4 (45 mm) if…

  • you want the lighter one: 56 g vs 68.3 g
Check price →

Specs from the makers’ own pages: Amazfit, Garmin.

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