COROS vs Garmin: VO2max compared
How COROS and Garmin estimate your VO2max, what each needs from you, what else they show and what independent studies say about accuracy.
| COROS | Garmin | |
|---|---|---|
| Called | VO2 Max | VO2 Max. |
| Algorithm | In-house EvoLab | Garmin in-house, built on Firstbeat Analytics |
| App | COROS app | Garmin Connect |
| From: Outdoor run | Yes | Yes |
| From: Walk | Not confirmed | Yes |
| From: Treadmill | No | No |
| From: Bike (power meter) | Yes | Yes |
| From: Resting test | Not confirmed | Not confirmed |
| From: All-day data | Not confirmed | Not confirmed |
| Fitness age | Not confirmed | Yes |
| Race predictor | Yes | Yes |
| Published accuracy studies | 0 | 5 |
| What you need to do | One continuous 25-minute outdoor run (Run or Track Run mode, no pauses) at or above 65% of heart rate reserve, then at least one such run every 90 days. Cycling: a steady 20+ minute ride with a power meter and heart rate. | Run outdoors with GPS for at least 10 minutes at 70%+ of max heart rate, or ride steadily at high intensity for 20+ minutes with a power meter. Set up your user profile and max heart rate. |
Key differences
- Fitness age: Garmin shows one (not confirmed for the other).
- Accuracy evidence: we found 0 published studies for COROS and 5 for Garmin.
How each one works
COROS: Running VO2 max uses heart rate and pace from your recent outdoor runs. Since October 2026 there is also a cycling VO2 max from rides with power and heart rate data.
Garmin: Compares your heart rate (wrist or chest strap) with your GPS pace on outdoor runs, or with power from a power meter on rides. It learns over several activities, so early numbers may be off.
Which is better for VO2max?
For VO2max specifically, the best device is the one that sees your hardest efforts: if most of your training is outdoor running, both give an estimate (both use outdoor run, bike (power meter)). If you cycle with a power meter, walk more than you run, or want a resting test, check those rows above. Whichever you choose, compare the number with itself over time and with the norms for your age.
Accuracy studies
COROS
No published, peer-reviewed validation found.
Garmin
- Howard et al., J Med Eng Technol, 2026: Forerunner 265 overestimated VO2max (43.95 vs 41.10 ml/kg/min at start) but mean absolute percent error stayed under 10%.
- Engel et al., Eur J Appl Physiol, 2026: Forerunner 245 underestimated VO2max by about 4-5 ml/kg/min (MAPE 7.2-7.9%); error was larger in highly trained athletes (MAPE 9.4-10.4%).
- Carrier et al., Sensors, 2025: fēnix 6 VO2max estimates were judged accurate (MAPE 7.05%, concordance 0.73 vs 30 s lab average).
- Düking et al., J Sports Sci Med, 2024: Forerunner 245 in youth soccer players: MAPE 5.58% after one run and 1.06% after a second run.
- Passler et al., Int J Environ Res Public Health, 2019: Forerunner 920XT had a MAPE of 7.3% but significantly underestimated VO2max.
Frequently asked questions
Is COROS or Garmin more accurate for VO2max?
Garmin has more published validation (5 vs 0 studies). Watch estimates are typically within several ml/kg/min of lab tests for groups, with larger individual errors, so use either one to track your trend.
Does COROS measure VO2max from outdoor run like Garmin?
Yes: both estimate from outdoor run, bike (power meter).
Which is better for VO2max: COROS or Garmin?
Pick the one whose data sources match how you train: COROS uses outdoor run, bike (power meter); Garmin uses outdoor run, walk, bike (power meter).
Built from official documentation (see each brand page for sources). Features vary by model and firmware. COROS and Garmin are trademarks of their owners; VO2max Health is independent and not affiliated with either.