Heart Rate Zone Calculator

How heart rate zones are calculated

This calculator uses the Karvonen method, which factors in your resting heart rate as well as your estimated max, producing what's called heart rate reserve (HRR). Zones are then set as percentages of that reserve, added back to your resting rate.

The Karvonen method is generally considered more personalized than simply taking a percentage of max heart rate alone, since two people with the same max heart rate can have very different fitness levels reflected in their resting heart rate.

For a deeper look at Zone 2 specifically, see the zone 2 heart rate calculator. If you already know your max heart rate from a real test, use the target heart rate calculator to set a single training target.

Where these numbers come from

The formulas and default values in this calculator are based on:

• Karvonen, M.J. et al. (1957) heart rate reserve method
• max heart rate estimated as 220 minus age

These are planning estimates for training purposes. Check with a coach, trainer, or physician before starting a new program or maxing out.