Heart Rate Zone Calculator

Maximum heart rate

Training zones are percentages of your maximum heart rate (MHR). The simplest estimate is 220 − age. The Tanaka formula, 208 − 0.7 × age, was derived from a much larger set of studies and is more accurate for people over 40. Both can be off by 10 beats or more for an individual; a supervised max test gives your true value.

The Karvonen method

If you enter a resting heart rate, the calculator uses the Karvonen formula, which bases zones on your heart rate reserve (the gap between resting and maximum). This adjusts for fitness: a fitter person with a lower resting rate gets more personalized zones.

Target HR = (Max HR − Resting HR) × intensity% + Resting HR

What each zone does

Zone	Intensity	Feels like	Benefit
1 Recovery	50–60%	Very easy	Warm-up, active recovery
2 Endurance	60–70%	Can hold a conversation	Aerobic base, fat use
3 Aerobic	70–80%	Moderate, short sentences	Cardio fitness
4 Threshold	80–90%	Hard, few words	Speed endurance
5 Maximum	90–100%	All-out	Short intervals, power

Many endurance coaches recommend spending about 80% of training time in zones 1–2 and 20% in zones 4–5. The "fat-burning zone" is real in the sense that a higher share of energy comes from fat at low intensity, but total calories burned are higher at harder efforts.

Frequently asked questions

What is a normal resting heart rate?

For adults it is typically 60–100 beats per minute. Well-trained athletes often have resting rates in the 40s or 50s.

What heart rate burns the most fat?

Zone 2 (roughly 60–70% of max) uses the highest proportion of fat for fuel, but higher-intensity exercise burns more total calories per minute.

Is 220 minus age accurate?

It is a rough population estimate. Individual maximum heart rates can differ by 10–20 beats. The Tanaka formula is slightly more accurate on average.

Last reviewed Oct 20, 2026. Results are estimates; check important decisions with a qualified professional.