Zone 2 Heart Rate Calculator
Zone 2 Heart Rate Calculator works out Maximum heart rate and Heart-rate reserve from Age, Maximum heart-rate equation and Measured maximum 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.
Your figures
Updates as you typeHow this is worked out
3 steps
- Tanaka (208 - 0.7 x age): HRmax = 208 - 0.7 x 40 = 180 bpm.
- Percentage of maximum: target = intensity x HRmax.
- Target zone 60-70%: 108 to 126 bpm.
Training zonestable
| zone | label | lowPercent | highPercent | lowBpm | highBpm |
|---|---|---|---|---|---|
| 1 | Very light - recovery | 50 | 60 | 90 | 108 |
| 2 | Light - aerobic base | 60 | 70 | 108 | 126 |
| 3 | Moderate - aerobic | 70 | 80 | 126 | 144 |
| 4 | Hard - threshold | 80 | 90 | 144 | 162 |
| 5 | Maximum - anaerobic | 90 | 100 | 162 | 180 |
Its 4 worked examples are re-run on every release, last on 15 September 2026. What changed
Sources and references
7 sources
What the Zone 2 Heart Rate 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 Zone 2 Heart Rate Calculator
Enter Age, Maximum heart-rate equation, Measured maximum heart rate 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, Measured maximum heart rate, Resting heart rate, Zone method and Target zone, lower intensity.
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.
See something wrong? Report a problem with this calculator
Frequently asked questions
What are my heart rate zones for my age?
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 Measured maximum heart rate and shown as Maximum heart rate, Heart-rate reserve and Resting heart rate used.
Is 150 bpm too high for zone 2?
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 the figures this page opens with — age 40 years — the maximum heart rate is 180 bpm. Put your own figures in their place and the working updates beside the result.
How do I calculate my heart rate zone?
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.
How long should you be in zone 3 heart rate?
On the figures this page opens with — age 40 years — the maximum heart rate is 180 bpm. No single number fits everyone: change any figure above and the answer updates as you type, with each step of the arithmetic beside it.
What information do I need for the Zone 2 Heart Rate Calculator?
You need Age, Maximum heart-rate equation, Measured maximum heart rate, Resting heart rate, Zone method, Target zone, lower intensity and Target zone, upper intensity. 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 Zone 2 Heart Rate 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.