Heart Rate Zone Calculator
See your five heart rate zones in beats per minute, the same zones your watch uses, from your age or a measured max heart rate. Add your resting heart rate for zones based on heart rate reserve.
Your details
Your results
Enter your age, or a measured max heart rate, to see your five zones.
Max heart rate
bpm
| Zone | % of max | Heart rate |
|---|---|---|
| Zone 1 · Very light | 50–60% | |
| Zone 2 · Light | 60–70% | |
| Zone 3 · Moderate | 70–80% | |
| Zone 4 · Hard | 80–90% | |
| Zone 5 · Maximum | 90–100% |
How to use it
- Enter your age. If you know your real max heart rate from a hard test, enter it too; it replaces the estimate.
- Optionally add your resting heart rate and choose zones by % of reserve (the Karvonen method).
- Read your zones in bpm. Use them to keep easy runs easy and hard sessions hard.
How it's calculated
Max heart rate. If you don’t enter a measured max, the calculator estimates it from your age. Choose the formula:
- Tanaka (2001): 208 − 0.7 × age, from a meta-analysis of 351 studies and a lab study of healthy adults. The default.
- Fox: 220 − age, the traditional rule of thumb.
- Gulati (2010): 206 − 0.88 × age, from treadmill tests in 5,437 women.
Zones by % of max. The five-zone model Polar and Garmin use by default:
| Zone | % of max |
|---|---|
| 1 · Very light | 50–60% |
| 2 · Light | 60–70% |
| 3 · Moderate | 70–80% |
| 4 · Hard | 80–90% |
| 5 · Maximum | 90–100% |
Zones by heart rate reserve (Karvonen). Heart rate reserve is max minus resting. Each zone boundary is:
resting + percentage × (max − resting)
Example: max 190, resting 60, 70% → 60 + 0.7 × 130 = 151 bpm.
Rounding. Zones are shown as whole beats that don’t overlap: each zone ends one beat below where the next one starts.
Limits. Age formulas describe averages; individual max heart rates vary widely. Heat, caffeine, sleep and some medicines (such as beta blockers) change heart rate. A measured max, or zones from a lactate threshold test, are more personal.
Sources
- Tanaka, H., Monahan, K. D., & Seals, D. R. (2001). Age-predicted maximal heart rate revisited. Journal of the American College of Cardiology, 37(1), 153–156.
- Gulati, M., Shaw, L. J., Thisted, R. A., Black, H. R., Bairey Merz, C. N., & Arnsdorf, M. F. (2010). Heart rate response to exercise stress testing in asymptomatic women. The St. James Women Take Heart Project. Circulation, 122(2), 130–137.
- Karvonen, M. J., Kentala, E., & Mustala, O. (1957). The effects of training on heart rate; a longitudinal study. Annales Medicinae Experimentalis et Biologiae Fenniae, 35(3), 307–315.
- Polar. Heart rate zones (five zones, 50 to 100% of maximum heart rate).
- Garmin. About heart rate zones (heart rate zone calculations).
Questions
How do I find my max heart rate?
The best way is a hard, supervised test, or the highest reading from an all-out race finish. Formulas only give an average for your age; your real max can be well above or below it.
Which max heart rate formula should I use?
Tanaka (208 − 0.7 × age) came from a large analysis of healthy adults and is the default here. 220 − age is the old rule. Gulati's formula was built from women's treadmill tests and gives women a lower estimate.
What's the difference between % of max and % of reserve?
Percent of max applies the percentage to your max heart rate alone. Heart rate reserve (max minus resting) applies it to the range above your resting rate, then adds your resting rate back. It gives higher numbers at the low end and adjusts for fitness, since fit people often have a lower resting rate.
Why don't my zones match my watch?
Your watch may use a different max heart rate, or zones based on reserve or lactate threshold. Set the same max and method on both and they'll match.
Updated November 9, 2026.