Heart Rate Zones Calculator
Enter your age — and resting HR for the more accurate Karvonen method.
Max HR
190 bpm
Warm-up
95–114 bpm
Fat burn
114–133 bpm
Aerobic
133–152 bpm
Anaerobic
152–171 bpm
Peak
171–190 bpm
How it works
We estimate max HR = 220 − age. Each zone is a percentage of heart rate reserve (Karvonen) or of max HR directly.
Formula
Karvonen: target HR = (max − rest) × % + rest
Worked example
Age 30, no resting HR: aerobic zone ≈ 133–152 bpm.
FAQ
- Best fat-burn zone?
- 60–70% of max HR — total calories matter more long-term.
- Measure resting HR?
- First thing in the morning before getting up.
- Is 220-age accurate?
- Rough estimate within ±10–15 bpm of actual max.