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  3. Heart rate zone calculator
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Heart rate zone calculator

Show maximum heart rate from the Fox, Tanaka, and Gellish formulas side by side with five training zones, switching to Karvonen zones when a resting rate is given.

This tool is in beta

Still being tested. If a result looks wrong, tell us.

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Enter an age to see the zones.

None of these formulas know anything about you besides your age. Fox (220 minus age) dates from 1971 and overreads the max for anyone past middle age; Tanaka and Gellish (208 and 207 minus 0.7 x age) fit the measured data better and run a few beats lower. Beta blockers and some other medications flatten heart rate response and make every number on this page meaningless for zone training. This is a planning aid, not medical advice.

The athlete

Age is a whole year count. Add a resting rate measured at true rest to switch the zones from percent-of-max to Karvonen reserve zones.

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