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HR Max Calculator

Hr max calculator works out Maximum heart rate and Heart-rate reserve from Age, Maximum heart-rate equation and Resting heart rate. The default figures on this page give maximum heart rate of 180 bpm; change any entry and the result, the working and the sources update together.

Maximum heart rate
180 bpm
Heart Rate Zone Calculator
Target zone, lower bound
115 bpm
Target zone, upper bound
137 bpm
Zone 2 lower bound
108 bpm
Zone 2 upper bound
126 bpm
Equation used
Tanaka (208 - 0.7 x age)
Zone method
Percentage of maximum heart rate
Published standard error of the equation
10.0 bpm
Worked out from Fox SM, Naughton JP, Haskell WL. Physical activity and the prevention of coronary heart disease. Ann Clin Res 1971;3:404-432. and 6 other sources.
Tanaka (208 - 0.7 x age) has a published standard error of about 10 bpm, so your true maximum could plausibly be 160 to 200 bpm.
Age-predicted maximum heart rate carries a standard error of roughly 7 to 12 beats per minute, so an individual can sit 20 bpm either side of the estimate. Beta blockers, other rate-limiting drugs, pacemakers, atrial fibrillation and heat or altitude all change these numbers. Anyone with a cardiac condition or symptoms on exertion should have their zones set by a clinician, not by an equation.

Your figures

Updates as you type
Tanaka and Gellish fit modern data better than the traditional 220 - age.
Taken on waking, before getting up. Required for the Karvonen method.

How this is worked out

3 steps
  1. Tanaka (208 - 0.7 x age): HRmax = 208 - 0.7 x 40 = 180 bpm.
  2. Percentage of maximum: target = intensity x HRmax.
  3. Target zone 64-76%: 115.2 to 136.8 bpm.
Training zonestable
zonelabellowPercenthighPercentlowBpmhighBpm
1Very light - recovery506090108
2Light - aerobic base6070108126
3Moderate - aerobic7080126144
4Hard - threshold8090144162
5Maximum - anaerobic90100162180

Its 4 worked examples are re-run on every release, last on 15 September 2026. What changed

Sources and references

7 sources
Fox SM, Naughton JP, Haskell WL. Physical activity and the prevention of coronary heart disease. Ann Clin Res 1971;3:404-432.
Astrand PO. Experimental Studies of Physical Working Capacity in Relation to Sex and Age. Copenhagen: Munksgaard, 1952.
Karvonen MJ, Kentala E, Mustala O. The effects of training on heart rate: a longitudinal study. Ann Med Exp Biol Fenn 1957;35:307-315
Origin of the heart-rate-reserve method: target = intensity x (HRmax - HRrest) + HRrest.
CDC, Target Heart Rate and Estimated Maximum Heart Rate
Moderate-intensity 64-76% and vigorous-intensity 77-93% of maximum heart rate.

What the hr max calculator calculates

Estimates maximum heart rate from age with a choice of published equations, then works out heart-rate reserve and the training zones on either percentage of maximum or the Karvonen heart-rate-reserve method.

How to use this hr max calculator

Enter Age, Maximum heart-rate equation and Resting heart rate. Maximum heart rate updates as you type. Change one figure at a time to see what drives the result.

How the result is worked out

Open “How this is worked out” beside the result for the step-by-step calculation behind Maximum heart rate, Heart-rate reserve and Resting heart rate used.

The method follows Fox SM, Naughton JP, Haskell WL. Physical activity and the prevention of coronary heart disease. Ann Clin Res 1971;3:404-432., Tanaka H, Monahan KD, Seals DR. Age-predicted maximal heart rate revisited. J Am Coll Cardiol 2001;37:153-156., Gellish RL et al. Longitudinal modeling of the relationship between age and maximal heart rate. Med Sci Sports Exerc 2007;39:822-829., Nes BM et al. Age-predicted maximal heart rate in healthy subjects: the HUNT Fitness Study. Scand J Med Sci Sports 2013;23:697-704. and Astrand PO. Experimental Studies of Physical Working Capacity in Relation to Sex and Age. Copenhagen: Munksgaard, 1952..

What you can compare

Change one input at a time to see how it affects Maximum heart rate, Heart-rate reserve and Resting heart rate used. The inputs you can vary are Age, Maximum heart-rate equation and Resting heart rate.

Understanding Maximum heart rate, Heart-rate reserve and Resting heart rate used

Age-predicted maximum heart rate carries a standard error of roughly 7 to 12 beats per minute, so an individual can sit 20 bpm either side of the estimate. Beta blockers, other rate-limiting drugs, pacemakers, atrial fibrillation and heat or altitude all change these numbers. Anyone with a cardiac condition or symptoms on exertion should have their zones set by a clinician, not by an equation.

Results are general information, not financial, tax, legal, medical or engineering advice. Check any decision that matters with a qualified professional.

Embed this calculator on your website

Copy this code into any page. The calculator appears with the figures currently entered, sizes itself to fit, and a small credit line links back here. Free, no account, no ads inside it, no tracking of your readers. Set your own figures and fixed fields; Personal removes the credit line, sets your colour and shows you which sites use it.

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Frequently asked questions

How do you calculate your HRmax?

Estimates maximum heart rate from age with a choice of published equations, then works out heart-rate reserve and the training zones on either percentage of maximum or the Karvonen heart-rate-reserve method. Open “How this is worked out” beside the result to see each step for your own figures.

What should my HRmax be?

Estimates maximum heart rate from age with a choice of published equations, then works out heart-rate reserve and the training zones on either percentage of maximum or the Karvonen heart-rate-reserve method. On this page it is computed from Age, Maximum heart-rate equation and Resting heart rate and shown as Maximum heart rate, Heart-rate reserve and Resting heart rate used.

What is my zone 2 if my max heart rate is 190?

It needs Age, Maximum heart-rate equation and Resting heart rate. Nothing else is required, and the figures stay in your browser.

What information do I need for the hr max calculator?

You need Age, Maximum heart-rate equation and Resting heart rate. The page opens with default figures that give maximum heart rate of 180 bpm, so you can see the scale before entering your own.

What does this hr max calculator show?

It shows Maximum heart rate, Heart-rate reserve, Resting heart rate used, Target zone, lower bound, Target zone, upper bound, Zone 2 lower bound, Zone 2 upper bound and Training zones, with the working and any warnings for your entries.

Can I check how the hr max calculator result was calculated?

Yes. The “How this is worked out” section shows the calculation steps, and the sources section identifies the references used for the method.

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