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Garmin Forerunner 55 vs Garmin Instinct 3 AMOLED (45 mm)
The specs that matter for triathlon, side by side, from each maker’s own published figures.
| Spec | Garmin Forerunner 55 | Garmin Instinct 3 AMOLED (45 mm) |
|---|---|---|
| GPS battery | 20 h | 32 h |
| Smartwatch battery | 14 days | 18 days |
| Triathlon / multisport mode | No | Yes |
| Onboard maps | No | No |
| Open-water GPS (our rating) | 3 / 5 | 5 / 5 |
| Weight | 37 g | 53 g |
| Screen | MIP | AMOLED |
| Price | See retailer | ~$349.99 |
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?
Garmin
Pick the Instinct 3 AMOLED (45 mm) if…
- you want the longer GPS battery: 32 h vs 20 h
- you want the longer smartwatch battery: 18 days vs 14 days
- you want a triathlon (multisport) mode
- you want better open-water GPS (our rating): 5 / 5 vs 3 / 5
Specs from the makers’ own pages: Garmin, Garmin.
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