How do I calculate my maximum heart rate by age?

The most recommended formula is Tanaka's: 208 − 0.7 × age. At 40, that gives 180 bpm. For women, the Gulati formula (206 − 0.88 × age) gives 171 bpm at the same age. The 220 − age formula is still everywhere but less accurate. All of them can be off by about 10 bpm; an exercise test remains the reference.

What is zone 2 and what heart rate should I run at?

Zone 2 is 60 to 70% of max HR (or of heart rate reserve with Karvonen). It is an easy effort where you can hold a conversation. For a 35 year old using Tanaka (max HR 184), it runs from about 110 to 128 bpm. Running in zone 2 often means slowing down a lot, or mixing running and walking at first: that is normal.

What is a normal resting heart rate?

For adults, the American Heart Association considers a resting rate between 60 and 100 bpm normal. Very fit people often sit between 40 and 60 bpm. A resting rate that is regularly above 100 bpm, or very low with fainting, dizziness or shortness of breath, should be checked by a doctor.

What is the difference between % of max HR and the Karvonen method?

The simple method applies a percentage to max HR alone. Karvonen starts from your resting rate and applies the percentage to your heart rate reserve (max HR − resting HR). Karvonen zones are higher in bpm and fit each person better, as long as your resting rate is measured properly.

Which heart rate zone burns the most fat?

In zone 2, fat makes up a larger share of the energy you use, but you burn fewer calories per minute than in zones 3 or 4. For weight loss, your weekly total and your diet matter more than the zone. A week mostly in zone 2 with one or two harder sessions, as the tool suggests, is a good balance.

I take beta blockers: do these zones apply to me?

No. Beta blockers and some other medicines slow the heart and lower your maximum heart rate, so the formulas no longer apply. Ask your doctor for suitable guidelines, often based on perceived effort (breathing, ability to talk) rather than bpm.

What heart rate zones does Muay Thai training reach?

Muay Thai mixes intensities. Skipping rope warm-ups and light shadow boxing often sit in zones 2 and 3. Two to three minute rounds on pads or the heavy bag often climb into zones 4 and 5, and the minute of rest between rounds is there to bring it down. A heart rate watch helps you check that you recover between rounds.

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Heart Rate Zones Calculator

Enter your age and, if you know it, your resting heart rate: the tool estimates your maximum heart rate with several published formulas, then your five zones in beats per minute, from recovery to VO2max. Each zone shows how it feels, what it does and real examples for walking, running, cycling and Muay Thai. You can measure your pulse right on the screen and get a balanced training week.

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How it works

Maximum heart rate (max HR) is the highest number of beats per minute your heart can reach during an all-out effort. It drops with age and varies a lot between people of the same age. Without an exercise test, it is estimated with a formula. The best known, 220 − age (Fox and Haskell, 1971), was never validated on a large sample and tends to underestimate max HR after 40. The Tanaka formula (208 − 0.7 × age), from a 2001 meta-analysis of 351 studies and almost 19,000 people, is now the most widely recommended. For women, Martha Gulati's team proposed 206 − 0.88 × age in 2010, based on more than 5,400 women. The tool also shows the Nes formula (211 − 0.64 × age, Norway's HUNT study, 2013) for comparison.
Whatever the formula, the error for one person is often around 10 beats per minute either way. That is why the tool picks Gulati by default for women and Tanaka for men, shows every other formula side by side, and lets you enter a measured max HR if you have one (an exercise test with a sports doctor, or the highest value a chest strap recorded during a very hard effort). A measured max HR is always more reliable than a formula.
Zones can be worked out in two ways. The simple method takes a percentage of max HR: 50 to 60% for zone 1, 60 to 70% for zone 2, then 70, 80 and 90%. The Karvonen method (1957) uses your resting heart rate: it finds your heart rate reserve (max HR − resting HR) and adds a percentage of that reserve to your resting rate. For example, with a max HR of 185 and a resting rate of 60, zone 2 starts at 60 + 0.6 × 125 = 135 bpm. Karvonen fits the zones better to very fit or less active people, but it needs a well measured resting rate.
To measure your resting heart rate, do it in the morning when you wake up, still lying down, or after five quiet minutes sitting, before coffee or a cigarette. Place your index and middle fingers on the inside of your wrist, on the thumb side (radial pulse), or gently on the side of your neck, never with your thumb, which has its own pulse. Count the beats for 15 seconds and multiply by 4, or for 30 seconds and multiply by 2; the tool gives you the timer. You can also tap the button on every beat: the result uses the median interval, so one missed tap does not matter. Repeat on three mornings and keep the average. For adults, the American Heart Association puts a normal resting rate between 60 and 100 bpm; it is often lower in athletes.
The suggested week follows the 80/20 principle described by exercise physiologist Stephen Seiler: about 80% of training time in zones 1 and 2, where you can still talk in full sentences, and 20% in harder zones. Hard sessions never fall on back-to-back days, the long session lands on the weekend and the interval session uses the 4 × 4 minute format studied by Jan Helgerud's team (2007). The tool also counts your minutes the way the World Health Organization does: it recommends 150 to 300 minutes of moderate activity a week, and one vigorous minute counts as two moderate ones. If you enter your weight, it estimates calories burned per hour in each zone with the Keytel et al. (2005) equations, which you can pair with the TDEE calculator.
Sources: Fox, Naughton and Haskell (1971); Tanaka, Monahan and Seals, Journal of the American College of Cardiology (2001); Gulati et al., Circulation (2010); Nes et al., Scandinavian Journal of Medicine & Science in Sports (2013); Karvonen, Kentala and Mustala (1957); Keytel et al., Journal of Sports Sciences (2005); Seiler, International Journal of Sports Physiology and Performance (2010); Helgerud et al., Medicine & Science in Sports & Exercise (2007); WHO guidelines on physical activity (2020); American Heart Association. This tool gives training guidelines, not medical advice: if you have heart disease or high blood pressure, are pregnant or take medicine that affects your heart rate, ask your doctor before training in the hard zones.

These tools give general information. They do not replace the advice of a doctor or a qualified professional.

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Frequently asked questions

How do I calculate my maximum heart rate by age?: The most recommended formula is Tanaka's: 208 − 0.7 × age. At 40, that gives 180 bpm. For women, the Gulati formula (206 − 0.88 × age) gives 171 bpm at the same age. The 220 − age formula is still everywhere but less accurate. All of them can be off by about 10 bpm; an exercise test remains the reference.
What is zone 2 and what heart rate should I run at?: Zone 2 is 60 to 70% of max HR (or of heart rate reserve with Karvonen). It is an easy effort where you can hold a conversation. For a 35 year old using Tanaka (max HR 184), it runs from about 110 to 128 bpm. Running in zone 2 often means slowing down a lot, or mixing running and walking at first: that is normal.
What is a normal resting heart rate?: For adults, the American Heart Association considers a resting rate between 60 and 100 bpm normal. Very fit people often sit between 40 and 60 bpm. A resting rate that is regularly above 100 bpm, or very low with fainting, dizziness or shortness of breath, should be checked by a doctor.
What is the difference between % of max HR and the Karvonen method?: The simple method applies a percentage to max HR alone. Karvonen starts from your resting rate and applies the percentage to your heart rate reserve (max HR − resting HR). Karvonen zones are higher in bpm and fit each person better, as long as your resting rate is measured properly.
Which heart rate zone burns the most fat?: In zone 2, fat makes up a larger share of the energy you use, but you burn fewer calories per minute than in zones 3 or 4. For weight loss, your weekly total and your diet matter more than the zone. A week mostly in zone 2 with one or two harder sessions, as the tool suggests, is a good balance.
I take beta blockers: do these zones apply to me?: No. Beta blockers and some other medicines slow the heart and lower your maximum heart rate, so the formulas no longer apply. Ask your doctor for suitable guidelines, often based on perceived effort (breathing, ability to talk) rather than bpm.
What heart rate zones does Muay Thai training reach?: Muay Thai mixes intensities. Skipping rope warm-ups and light shadow boxing often sit in zones 2 and 3. Two to three minute rounds on pads or the heavy bag often climb into zones 4 and 5, and the minute of rest between rounds is there to bring it down. A heart rate watch helps you check that you recover between rounds.

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