Free calculator
Heart-rate zone calculator
Your five training zones from your age, fitted to you with your resting heart rate. Worked out in your browser; nothing is sent anywhere.
Work out your zones
Maximum heart rate
—bpm
| Zone | bpm | From % of max |
|---|---|---|
| 1 · Very light | — | 50% |
| 2 · Light | — | 60% |
| 3 · Moderate | — | 70% |
| 4 · Hard | — | 80% |
| 5 · Maximum | — | 90%+ |
Enter your age to see your zones.
How it works
Your maximum heart rate is estimated from your age with Tanaka's formula, or the highest rate you've actually seen if that's higher. The five zones are the bands from Edwards' heart-rate zones. With a resting heart rate they use your heart-rate reserve (the Karvonen method), as the American College of Sports Medicine describes, so the zones fit your own fitness.
Max = 208 − 0.7 × age
Without a resting rate: zones start at 50, 60, 70, 80 and 90 % of max
With one: resting + 20, 35, 50, 65 and 80 % of (max − resting)
The reserve shares are the ones ACSM's intensity table pairs with those percentages of max, so zone 3 still means moderate and zone 4 hard. A resting rate is used when it's between 30 and 110 bpm and at least 40 beats under your max.
- Tanaka H, Monahan KD, Seals DR (2001). Age-predicted maximal heart rate revisited. Journal of the American College of Cardiology, 37(1), 153–156. doi.org/10.1016/S0735-1097(00)01054-8
- American College of Sports Medicine; Liguori G, ed. (2021). ACSM's Guidelines for Exercise Testing and Prescription, 11th edition. Wolters Kluwer. openlibrary.org
- Edwards S (1993). The Heart Rate Monitor Book. Polar Electro. openlibrary.org
Questions
How do I work out my heart-rate zones?
Estimate your maximum heart rate (208 − 0.7 × your age), then take 50, 60, 70, 80 and 90 % of it as the start of zones 1 to 5. If you know your resting heart rate, start each zone at resting + 20, 35, 50, 65 or 80 % of the gap between resting and max instead.
Why add my resting heart rate?
Two people of the same age can have very different resting rates. The heart-rate reserve method counts from yours, so a fitter heart with a low resting rate gets zones that match how hard it's really working.
Which zone should I train in?
Easy and long sessions usually sit in zones 2 and 3; zones 4 and 5 are for short, hard efforts. Endurance plans often keep most training easy, with a little hard work on top.
Is the age formula right for me?
It's an average, and real maximums vary by several beats either way. If a hard workout has shown you a higher number, enter it. If you have a heart condition or take medicine that changes your heart rate, such as a beta blocker, ask your doctor which zones are right for you before training by heart rate.
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