Health / 06
Heart Rate Zone Calculator
Work out your five heart rate training zones from your age or measured maximum, as a percentage of maximum heart rate or with the Karvonen method, which uses your resting heart rate too.
Heart Rate Zone Calculator: Maximum heart rate is estimated with Tanaka's formula, 208 − 0.7 × age, from a 2001 analysis of 351 studies, or the older 220 − age, unless you enter a measured value. The zones are 10% bands from 50% to 100%: of maximum heart rate, or with the Karvonen method of heart rate reserve, the gap between maximum and resting, added to your resting rate. Runs 100% locally in your browser with zero server file uploads.
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Maximum 184 bpm
Estimate| Zone | Intensity | Heart rate (bpm) |
|---|---|---|
| 1 | Very light: warm-up and recovery (50–60%) | 92–110 |
| 2 | Light: easy endurance (60–70%) | 110–128 |
| 3 | Moderate: aerobic fitness (70–80%) | 128–147 |
| 4 | Hard: threshold (80–90%) | 147–165 |
| 5 | Maximum: short intervals (90–100%) | 165–184 |
Age formulas are averages: a real maximum can differ by 10 to 20 beats a minute either way. If you have a heart condition or take medicine that slows the heart, such as a beta blocker, ask your doctor for your own targets.
The five zones
Zone 1 is a warm-up or recovery effort; zone 2 is easy endurance, a pace you could keep up for hours while talking; zone 3 is steady aerobic work where talking becomes broken; zone 4 is around the threshold, hard but sustainable for 20 to 60 minutes; zone 5 is near maximum, held only for short intervals.
Many endurance plans keep about four-fifths of training time in the easy zones and add a few hard sessions. Running plans often give paces instead of heart rates; the pace calculator converts between them and finish times.
Measuring your own numbers
Resting heart rate is best taken lying down just after waking, over a full minute, on a few mornings. A chest strap is more accurate than a wrist sensor during hard intervals. A measured maximum, from a supervised test or the highest value you see in an all-out race finish, beats any formula.
How to use it
- Enter your age, or the maximum heart rate you have measured.
- Choose % of maximum, or Karvonen and enter your resting heart rate.
- Read the beats-per-minute range for each zone.
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Frequently asked questions
Which maximum heart rate formula is more accurate?
Tanaka's 208 − 0.7 × age fitted the data from 351 studies better than 220 − age, which overestimates the maximum of younger people and underestimates that of older people. Both are averages, though: an individual's real maximum can differ by 10 to 20 beats a minute, and only a maximal test measures it.
What is the Karvonen method?
It sets zones within your heart rate reserve, the range between resting and maximum heart rate, then adds the resting rate back. Fitter people with a low resting rate get higher zone figures than the plain percentage of maximum gives, which usually matches how hard the effort feels better.
Which zone burns the most fat?
Easy zones burn a higher share of fat, but harder zones burn more energy in total per minute. For weight, total energy over the week matters more than the zone; most training plans keep most time in zones 1 and 2 and add some harder sessions.
Is it safe for me to train in the top zones?
Zones 4 and 5 are hard efforts. If you have a heart condition, high blood pressure, or take medicine that changes the heart rate, such as a beta blocker, or you are starting exercise after a long break, talk to your doctor first.
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