LazyTools

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❤️ Heart Rate Zone Calculator

Enter your age to get your five training heart-rate zones — add a resting heart rate for personalised Karvonen zones based on your heart-rate reserve.

Estimated maximum heart rate187 bpm· zones via Karvonen (HR reserve)
Zone 1Very light — warm-up, recovery (50–60%)124–136 bpm
Zone 2Light — fat burn, base endurance (60–70%)136–149 bpm
Zone 3Moderate — aerobic, stamina (70–80%)149–162 bpm
Zone 4Hard — anaerobic threshold (80–90%)162–174 bpm
Zone 5Maximum — VO₂ max, sprints (90–100%)174–187 bpm

Max-HR formulas are population estimates — an actual max can vary ±10–12 bpm. With a resting HR, zones use the Karvonen heart-rate-reserve method: target = (max − rest) × %intensity + rest. Not medical advice. 🔒 In your browser.

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How the heart rate zone calculator works

First the tool estimates your maximum heart rate from age — Tanaka (208 − 0.7 × age), the traditional 220 − age, or Gulati (206 − 0.88 × age) for women. Without a resting HR, each zone is a percentage band of that maximum. With a resting HR, it uses the Karvonen (heart-rate-reserve) method: target = (max − rest) × intensity + rest, which better reflects your individual range.

Maximum-heart-rate formulas are population averages — an individual's true max can be 10–12 bpm higher or lower. For serious training, a lab or field max-HR test is more accurate. This is general fitness information, not medical advice.

Frequently asked questions

How do I calculate my heart rate zones?

Estimate your maximum heart rate (e.g. Tanaka: 208 − 0.7 × age), then take percentage bands of it — Zone 2 is 60–70%, Zone 4 is 80–90%, and so on. With a resting HR, the Karvonen method personalises the bands.

What is the Karvonen formula?

It sets target heart rate using your heart-rate reserve: target = (max HR − resting HR) × intensity% + resting HR. Because it accounts for your resting HR, it gives more individual zones than plain percentage-of-max.

What is Zone 2 training?

Zone 2 is a light, conversational intensity — roughly 60–70% of maximum heart rate — used to build aerobic base and fat-burning endurance. Much of an endurance athlete's training is done here.

Which max heart rate formula should I use?

Tanaka (208 − 0.7 × age) is generally more accurate than the older 220 − age across ages; Gulati (206 − 0.88 × age) was derived specifically for women. All are estimates — an actual tested max is best.

Is 220 minus age accurate?

It's a rough rule of thumb that can be off by 10–20 bpm for an individual. It's fine as a starting point, but Tanaka is usually closer, and a measured max HR is more reliable than any formula.

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