Garmin VO2max: how it works.
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.
What counts towards your VO2max
Estimated from: Outdoor run, Walk, Bike (power meter). Not used: Treadmill.
What you need to do
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.
How it is shown
A number, a description and a spot on a colour gauge: purple Superior, blue Excellent, green Good, orange Fair, red Poor. Garmin Connect shows how you rank for your age and sex.
Related features
- Fitness age: yes
- Race predictor: yes
- Training status
- HRV status
- Lactate threshold
- Endurance score
- Hill score
- Recovery time
- Real-time stamina
- Heat and altitude acclimation
Models
fēnix 9 · fēnix 8 · Forerunner 970 · Forerunner 570 · Forerunner 265 · vívoactive 6
How accurate is it?
| Study | Finding |
|---|---|
| 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. |
Running and cycling have separate estimates. fēnix 9 also gives an indoor rowing estimate (with a power meter). Indoor runs do not give an estimate. Trail and ultra runs can be excluded. When you adapt to heat or altitude the watch shows a corrected value. Fitness age uses age, BMI (or body fat), resting heart rate and vigorous activity, not the VO2 max number itself.
Frequently asked questions
How does Garmin calculate VO2max?
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. 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.
How accurate is Garmin VO2max?
5 published studies have tested it: Forerunner 265 overestimated VO2max (43.95 vs 41.10 ml/kg/min at start) but mean absolute percent error stayed under 10%.
Which Garmin devices show VO2max?
Examples: fēnix 9, fēnix 8, Forerunner 970, Forerunner 570, Forerunner 265, vívoactive 6. Support depends on model and firmware.
Check your number against the norms for your age, estimate it with the VO2max calculator, or turn it into race times and paces.
Sources
- Forerunner 970 Owner's Manual (PDF)
- fēnix 9 Series Owner's Manual - About VO2 Max. Estimates
- fēnix 8 Series Owner's Manual - About VO2 Max. Estimates
- vívoactive 5 Owner's Manual - Getting Your VO2 Max. Estimate
- vívoactive 6 Owner's Manual (PDF)
- Forerunner 265 Owner's Manual - About VO2 Max. Estimates
- Forerunner 570 Owner's Manual - VO2 Max. Standard Ratings
- Garmin press release: Garmin acquires Firstbeat Analytics (2020)
Garmin is a trademark of its owner. VO2max Health is independent and not affiliated with Garmin. Features vary by model and firmware.