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Heart Rate Zone Calculator

A free Heart Rate Zone Calculator that finds your five training zones (recovery, endurance, tempo, threshold, max) using your age and optional resting heart rate. Choose between the classic 220-age formula and the Tanaka equation, and apply the Karvonen heart-rate-reserve method for personalized zones. See exact bpm ranges with a color-coded zone bar. Everything runs in your browser — private and mobile-friendly.

Age

Resting HR (bpm)

Max HR Formula

Karvonen Method

Uses heart-rate reserve (max − resting) for personalized zones

Max HR

187

bpm

Resting

bpm

Reserve

127

bpm

Method

Karvonen (max 187 − rest 60)

Zone 1 50–60%

Very light · recovery · warm-up

124–136bpm

Zone 2 60–70%

Light · endurance · fat utilization

136–149bpm

Zone 3 70–80%

Moderate · tempo · aerobic

149–162bpm

Zone 4 80–90%

Hard · threshold · lactate clearance

162–174bpm

Zone 5 90–100%

Maximum · VO₂ max · sprint

174–187bpm

Heart-rate estimates are educational. If you take heart-rate-altering medications or have cardiac conditions, consult a healthcare professional before training by zones.

Frequently Asked Questions

Everything you need to know about heart rate training zones

How are heart rate zones calculated?

Zones are percentages of your maximum heart rate (or heart-rate reserve with Karvonen). Common models: 220−age and Tanaka (208 − 0.7×age). Karvonen uses (max − resting) × % + resting for a more personalized range.

What are the 5 heart rate zones?

Z1 (50–60%) very light recovery, Z2 (60–70%) light endurance/fat burn, Z3 (70–80%) moderate tempo/aerobic, Z4 (80–90%) hard threshold, Z5 (90–100%) maximum effort. Beginners should spend most training in Z1–Z2.

Should I use 220-age or Tanaka?

Tanaka (208 − 0.7×age) is generally more accurate for adults. 220−age is simpler but tends to overestimate max HR for older adults. For the most accurate results, use your resting heart rate with the Karvonen method.

Is my data private?

Yes. All calculations happen in your browser. Your age and heart-rate data never leave your device.

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