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Heart Rate Zone Calculator
Enter your age and resting heart rate, and this calculator estimates your max heart rate and lays out your five Karvonen training zones in beats per minute, so every workout hits the right intensity.
-Max heart rate
-Resting heart rate
The Karvonen method
Max heart rate is estimated as 220 minus age. Subtract your resting heart rate to get heart rate reserve (HRR), the range your heart can work through. Each training zone is a percentage of that reserve added back to your resting rate, which personalizes the zones better than raw percentages of max.
Worked example
Age 30, resting 60 bpm.
- Max = 220 - 30 = 190 bpm.
- HRR = 190 - 60 = 130 bpm.
- Zone 2 (60-70%) = 60 + 130 x 0.60 to 60 + 130 x 0.70 = 138-151 bpm.
How to use the zones
Zone 1 is for warm-ups and recovery, Zone 2 builds aerobic base and burns fat, Zone 3 improves cardio fitness, Zone 4 trains your lactate threshold, Zone 5 is for short maximum efforts. Most endurance training happens in Zones 1 to 3.
Planning estimate only. Results use the list prices shown and may differ from your actual bill. Terms
Frequently asked questions
How accurate is 220 minus age?
It is a rough population estimate that can be off by 10 to 20 beats. A lab or field test gives a truer max. The zones are still useful as relative targets.
What if my resting heart rate is very low or very high?
Low resting rates are normal in trained athletes. Very high resting rates can indicate stress, illness, or overtraining. See a doctor if yours stays above 100.
Why use heart rate reserve instead of percent of max?
Reserve accounts for your fitness level through your resting rate, so two people the same age with different fitness get different, more realistic zones.
Should beginners train in Zone 5?
No. Zone 5 is for short, hard intervals done by conditioned athletes. Beginners should spend most of their time in Zones 1 and 2.