Target Heart Rate Calculator
Work out your maximum heart rate and all five training zones in bpm, using percentage of max HR or the Karvonen reserve method.
Enter your age — the zones update as you type.
- Maximum heart rate
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- Heart rate reserve
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- Fat-burn zone (Zone 2)
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- Method
- % of max HR
| Zone | Intensity | Target (bpm) | Feels like |
|---|---|---|---|
| Zone 1 — Recovery | 50–60% | —–— | Very easy, full conversation |
| Zone 2 — Endurance | 60–70% | —–— | Easy, can talk in sentences |
| Zone 3 — Aerobic | 70–80% | —–— | Steady, short sentences only |
| Zone 4 — Threshold | 80–90% | —–— | Hard, a few words at a time |
| Zone 5 — Maximum | 90–100% | —–— | All-out, no talking |
How it works
The calculator first estimates your maximum heart rate. The classic Fox formula is
220 − age; the newer Tanaka formula (208 − 0.7 × age) fits older
adults better, and the Gulati formula (206 − 0.88 × age) was derived from women.
If you have done a real max-effort test or read a max from a chest strap, pick “I know my max
HR” and type it in — a measured value always beats a formula.
From there the five training zones are simple percentages. With “% of maximum heart rate” each
zone is a straight share of your max, so Zone 2 for a max of 190 bpm runs 114–133 bpm. With the
Karvonen method the percentages are applied to your heart rate reserve (max minus
resting) and your resting rate is added back: target = resting + % × (max − resting).
Karvonen needs a resting heart rate — measure it lying still just after waking — and gives
slightly higher, more individual numbers. Everything is worked out in your browser with plain
JavaScript: nothing about your heart, age or workouts leaves the device, and there are no ads
or sign-ups.
These heart rate zones are estimates from age-based formulas, not medical advice. Real maximum heart rates vary by roughly ±10–12 bpm from any formula, and medication such as beta blockers changes them further. Ask a doctor or a qualified coach before starting hard training, especially if you have a heart condition.
Frequently asked questions
How do I calculate my heart rate zones?
First estimate your maximum heart rate. The classic Fox formula is 220 minus your age, so a 30-year-old lands on about 190 bpm; the Tanaka formula (208 − 0.7 × age) fits older adults better and Gulati (206 − 0.88 × age) was derived from women. Then take percentages of that max: Zone 1 is 50–60%, Zone 2 60–70%, Zone 3 70–80%, Zone 4 80–90% and Zone 5 90–100%. For that 190 bpm max, Zone 2 runs 114–133 bpm. This calculator does all five zones at once and lets you type a measured max instead of using a formula.
What is the Karvonen method and should I use it?
Karvonen applies the zone percentages to your heart rate reserve — your maximum heart rate minus your resting heart rate — and then adds the resting rate back: target = resting + % × (max − resting). With a max of 190 bpm and a resting rate of 60 bpm the reserve is 130 bpm, so Zone 2 becomes 138–151 bpm instead of 114–133 bpm. Because it accounts for your fitness, Karvonen gives more individual (and usually higher) numbers, but it needs an accurate resting heart rate measured lying still just after waking.
Which zone actually burns fat, and how accurate are these numbers?
Zone 2, roughly 60–70% of your maximum, is the classic fat-burning zone: the highest share of the calories you burn comes from fat there, though harder efforts still burn more total calories per minute. Treat every number here as an estimate — age-based formulas scatter by about ±10–12 bpm between individuals, and beta blockers or other medication shift your heart rate further. Use the zones as a starting point, adjust them against how the effort actually feels, and speak to a doctor or coach before hard training if you have a heart condition.