Heart Rate Zone Calculator
Train smarter with heart-rate zones. Enter your age (and optionally resting heart rate) to get your max HR and five target zones.
Example: with Age 35 yrs · Resting heart rate 60 bpm → Max heart rate: 185 bpm.
- Zone 2 (60–70%) — fat burn135–148 bpm
- Zone 3 (70–80%) — cardio148–160 bpm
- Zone 4 (80–90%) — threshold160–173 bpm
Computed by the calculator below using its default values. Change any input to see your own numbers.
Heart-rate monitors and training apps
Learn moreWhy zones matter
Different intensities train different systems: easy Zone 2 builds aerobic base and burns fat efficiently, while hard Zone 4–5 work sharpens speed and threshold. Most endurance plans spend the majority of time in lower zones — training by heart rate keeps easy days truly easy and hard days hard.
How it’s calculated & sources
Maximum heart rate ≈ 220 − age. Zones are percentages of max, or — if you enter resting HR — the more precise Karvonen method using heart-rate reserve (max − rest).
Benchmark: max HR ≈ 220 − age; the Karvonen method refines zones using your resting heart rate.
Results update as you type and are general estimates, not personalized financial, tax, medical or legal advice. Verify with a professional.
Frequently asked questions
Is 220 minus age exact?
It’s an estimate with real individual variation. A lab test or a max-effort field test gives a more accurate number; the formula is fine for general training.
What’s the benefit of the Karvonen method?
It accounts for your fitness via resting heart rate, giving more personalized zones than the simple percentage-of-max approach.