Amazfit T-Rex 3 vs Garmin Fénix 8 AMOLED 47 mm

Amazfit T-Rex 3 (42 h GPS, 68 g) vs Garmin Fénix 8 AMOLED 47 mm (47 h GPS, 59 g). Side-by-side spec comparison: battery, weight, maps, multi-band GPS and price. Which GPS watch should you buy?

Amazfit T-Rex 3AmazfitAmazfit T-Rex 3

Ultra-rugged outdoor watch with dual-band GPS, offline maps and a 2,000-nit AMOLED display, at a mid-range price. 42 h in maximum-accuracy mode and up to 27 days in daily use. Military standard, 100 m water resistance and onboard music. Garmin Instinct-style toughness for far less.

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Garmin Fénix 8 AMOLED 47 mmGarminGarmin Fénix 8 AMOLED 47 mm

Garmin's flagship multisport watch: AMOLED display, topo maps, multi-band GPS, LED flashlight, speaker and microphone. 47 h in GPS mode (35 h multi-band) and 16 days in smartwatch mode. Rugged case with sapphire glass for mountain ultras and multi-day adventures.

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Spec-by-spec comparison

SpecAmazfit T-Rex 3Garmin Fénix 8 AMOLED 47 mm
GPS battery42 h47 h
Multi-band batteryYes35 h
Smartwatch27 days16 days
Weight68 g59 g
Maps
Multi-band
Music
DisplayAMOLEDAMOLED
PriceEntryFlagship

GPS battery = each manufacturer's standard GPS mode; multi-band = dual-frequency (maximum accuracy). On Suunto, Polar Grit and Amazfit T-Rex the GPS figure already corresponds to dual-band mode. Figures verified against the manufacturer.

Verdict

For maximum autonomy on long ultras, Garmin Fénix 8 AMOLED 47 mm lasts longer in GPS mode. If you want the lightest watch on your wrist, go for Garmin Fénix 8 AMOLED 47 mm. On budget, Amazfit T-Rex 3 is the more affordable option.

View on Amazon: Amazfit T-Rex 3View on Amazon: Garmin Fénix 8 AMOLED 47 mm

Frequently asked questions

Which lasts longer, Amazfit T-Rex 3 or Garmin Fénix 8 AMOLED 47 mm?
Amazfit T-Rex 3 offers 42 h of GPS battery and Garmin Fénix 8 AMOLED 47 mm offers 47 h, so Garmin Fénix 8 AMOLED 47 mm lasts longer for long efforts.
Which one is lighter?
Amazfit T-Rex 3 weighs 68 g and Garmin Fénix 8 AMOLED 47 mm weighs 59 g; Garmin Fénix 8 AMOLED 47 mm is the lighter of the two.
Do both have onboard maps?
Yes, both Amazfit T-Rex 3 and Garmin Fénix 8 AMOLED 47 mm include onboard topo maps.
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