Free tool
Heart rate zone calculator
Enter your age, or a measured maximum if you have one, and get your five training zones in beats per minute. No account, no email, nothing leaves your browser.
Estimated maximum heart rate
| Zone | Purpose | % of max | Your range |
|---|
How these zones are calculated
Each zone is a percentage band of your maximum heart rate. Zone 1 runs from 50 to 60 percent, zone 2 from 60 to 70, and so on up to zone 5 above 90 percent. This is the five-zone model used by Apex Health: Recovery Coach and by most mainstream training systems, though you will find slight variations between coaches and platforms, which is normal.
If you have not measured your maximum heart rate directly, the calculator estimates it. Three formulas are offered:
- Tanaka (208 − 0.7 × age) is the default. It was derived from a large meta-analysis and generally performs better than the older formula, particularly for people over 40.
- Gulati (206 − 0.88 × age) was derived specifically from a large cohort of women and tends to fit better than male-derived equations.
- Fox (220 − age) is the one everyone has heard of. It is simple and widely used, but it systematically overestimates for younger adults and underestimates for older ones.
All three are population estimates. Individual maximum heart rates scatter around any formula with a standard deviation of roughly 10 to 12 beats per minute, which means a formula could easily be 20 bpm wrong for you specifically.
Sanity-check your zones with the talk test
Because formula estimates are imprecise, verify zone 2 by feel. At a genuine zone 2 effort you should be able to speak in complete sentences without gasping. If you cannot finish a sentence comfortably, you are above it, whatever the watch says.
If the talk test and the calculated band disagree consistently, trust the talk test and adjust your assumed maximum until the numbers match your experience. See our guide to zone 2 training for why this band matters so much.
Common questions
How do I find my real maximum heart rate?
The only accurate method is a maximal effort test, ideally supervised. A common field protocol is a thorough warm-up followed by several hard uphill efforts of two to three minutes with the final one taken to true exhaustion; the highest value recorded is a reasonable estimate. This is genuinely demanding and is not appropriate if you have any cardiovascular risk factors, so speak to a doctor before attempting it. In practice, the highest heart rate your watch has recorded during a hard race or session is often a good enough proxy.
Why do my watch's zones differ from this calculator?
Most watches let you set zones manually or calculate them from a maximum heart rate you have configured, and some default to percentages of heart rate reserve rather than of maximum heart rate, which produces different boundaries. Check which model your device uses and which maximum it has stored.
Should I use heart rate reserve instead?
Heart rate reserve, which factors in your resting heart rate using the Karvonen method, is arguably more individualised. It generally shifts the zone boundaries upward compared to a straight percentage of maximum. Either model works provided you use it consistently; the important thing is not to mix them.
Is this calculator free?
Yes, entirely, with no account, no email, and no advertising. It runs as JavaScript in your browser, so the age and heart rate you type never leave your device and are never sent to us or anyone else.
Wake up to a verdict, not a spreadsheet.
Apex Health: Recovery Coach turns the Apple Health data you already generate into one clear decision each morning. Free, private, and entirely on your device.
Apex Health: Recovery Coach provides general wellness and fitness information computed from your own data. It is not a medical device and does not diagnose, treat, or prevent any condition. Always consult a qualified professional for medical concerns.