Heart Rate Zone Calculator
Max heart rate by the Tanaka, 220−age or Gellish formula and five training zones in bpm — by percent of max or the Karvonen heart-rate-reserve method.
Heart Rate Zone Calculator: with the default inputs, maximum heart rate is 184.
bpm
- Heart-rate reserve
- 124Max − resting. The Karvonen method scales zones across this range.
- Zone 2 (aerobic base)
- 110–128 bpm
- Zone 4 (threshold)
- 147–165 bpm
- ACSM 'moderate' intensity
- 117–139 bpm64–76% of max HR — the range behind the 150-minutes-a-week guideline.
Assumptions
- Zones use the common five-zone model at 50/60/70/80/90% boundaries; some coaches and devices draw them differently.
- Age-based max heart rate carries a standard deviation of roughly 10 bpm.
- Not adjusted for medications (e.g. beta-blockers), heat, altitude or illness. Anyone with heart disease should get zones from a clinician.
| Zone | Name | Intensity | From (bpm) | To (bpm) | How it feels / use |
|---|---|---|---|---|---|
| Zone 1 | Very light / recovery | 50–60% | 92 | 110 | Easy conversation; warm-ups, cool-downs, active recovery |
| Zone 2 | Light / aerobic base | 60–70% | 110 | 128 | Can talk in full sentences; long easy runs and rides, fat oxidation |
| Zone 3 | Moderate / tempo | 70–80% | 128 | 147 | Short sentences only; steady 'comfortably hard' efforts |
| Zone 4 | Hard / threshold | 80–90% | 147 | 165 | A few words at a time; lactate threshold intervals |
| Zone 5 | Maximum / VO₂max | 90–100% | 165 | 184 | Can't talk; short intervals of 30 s to 3 min |
How this is worked out
The formula
Max HR (Tanaka 2001) = 208 − 0.7 × age Max HR (classic) = 220 − age Max HR (Gellish 2007) = 207 − 0.7 × age % of max: zone bpm = max HR × % Karvonen: zone bpm = resting HR + (max HR − resting HR) × % Zones: 1 = 50–60% · 2 = 60–70% · 3 = 70–80% · 4 = 80–90% · 5 = 90–100%
Open How it’s calculated above to see this worked through with your own numbers.
What you enter
- Age
- A number.from 10 to 100 · whole numbers only · defaults to 35
- Max heart rate formula
- Choose one of 4 options.Tanaka: 208 − 0.7 × age (recommended) · Classic: 220 − age · Gellish: 207 − 0.7 × age · I know my max (enter under More options)
- Zone method
- Choose one of 2 options.Percent of max heart rate · Karvonen — percent of heart-rate reserve (uses resting HR)
- Resting heart rate(under More options)
- Measured lying down on waking. Needed for the Karvonen method.from 30 to 120 · whole numbers only · defaults to 60
- Measured max heart rate(under More options)
- From a max test or the peak of an all-out race. Used only when 'I know my max' is selected.from 100 to 230 · whole numbers only · defaults to 185
What you get back
- Maximum heart ratemain answer
- bpm
- Heart-rate reserve
- Max − resting. The Karvonen method scales zones across this range.
- Zone 2 (aerobic base)
- Zone 4 (threshold)
- ACSM 'moderate' intensity
- 64–76% of max HR — the range behind the 150-minutes-a-week guideline.
What this assumes
- Zones use the common five-zone model at 50/60/70/80/90% boundaries; some coaches and devices draw them differently.
- Age-based max heart rate carries a standard deviation of roughly 10 bpm.
- Not adjusted for medications (e.g. beta-blockers), heat, altitude or illness. Anyone with heart disease should get zones from a clinician.
About this calculator
Heart rate zones turn a vague instruction like "go easy" into a number you can hold. Each zone corresponds to a different physiological demand — from the fat-burning, mitochondria-building aerobic work of zone 2 to the VO₂max intervals of zone 5 — and most well-designed endurance programs spend about 80% of time in the low zones and 20% in the high ones.
Estimating maximum heart rate
Everything hangs on your max, and "220 − age" is the weakest link. It was never derived from a proper study — Fox and colleagues sketched it from a handful of data points in 1971 — and it overestimates for young adults and underestimates for older ones. Tanaka's 2001 meta-analysis of 351 studies produced 208 − 0.7 × age, which is the default here; Gellish's 2007 longitudinal study landed on nearly the same line. Even the better formulas carry a standard deviation of about 10 bpm, so if you have a real max from a hard race finish or a supervised test, choose "I know my max" and enter it.
Percent of max vs. Karvonen
Percent-of-max zones are simple but ignore fitness. The Karvonen method scales zones across your heart-rate reserve — the gap between resting and maximum — so a fit person with a resting rate of 48 gets different zones from someone at 75 with the same max. Enter your resting rate under More options and switch the method; it's the version the ACSM uses for exercise prescription.
The zones
- Zone 1 (50–60%): recovery. Warm-ups, cool-downs, easy days.
- Zone 2 (60–70%): aerobic base. Conversational pace; the bulk of endurance training. Builds capillaries, mitochondria and fat oxidation.
- Zone 3 (70–80%): tempo. Comfortably hard; useful but easy to overuse.
- Zone 4 (80–90%): threshold. Around the lactate turn-point; 10–40-minute efforts and cruise intervals.
- Zone 5 (90–100%): VO₂max. Short, very hard intervals.
Caveats
Heart rate lags effort by a minute or two, drifts upward in heat and dehydration, and is blunted by beta-blockers and some other medications. On short intervals, pace or power is a better guide. And if your heart rate at a given effort is suddenly 10 bpm higher than usual, that's often illness or fatigue talking — listen to it.
Frequently asked questions
▸How do I calculate my maximum heart rate?
Best is a measured value from a maximal test or a hard race finish. Otherwise use Tanaka's formula, 208 − 0.7 × age, which is better validated than 220 − age. Expect ±10 bpm either way.
▸What is zone 2 heart rate?
60–70% of your maximum (or 60–70% of heart-rate reserve with Karvonen). For a max of 185, that's about 111–130 bpm. You should be able to hold a conversation.
▸Is 220 minus age accurate?
Not very. It has no solid research basis and is off by more than 10 bpm for about a third of people. Tanaka (208 − 0.7 × age) fixes the systematic bias, but individual variation remains.
▸What's the Karvonen formula?
Target HR = resting HR + (max HR − resting HR) × intensity. It accounts for your resting heart rate, so zones reflect your fitness rather than just your age.
▸What heart rate burns the most fat?
The highest percentage of energy from fat comes in zone 2, but higher zones burn more total calories per minute. For weight loss, total energy expenditure matters more than the fuel mix.
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