Prescribing conditioning off "moderate" and "hard" is a blunt instrument. Heart rate zones give you an objective, individual way to set intensity, so recovery work stays genuinely easy and threshold work actually reaches threshold.

This free calculator turns an athlete's age and resting heart rate into their five training zones in beats per minute, using either the percentage of maximum heart rate method or the more individualised Karvonen (heart rate reserve) method. It estimates maximum heart rate with the Tanaka equation (208 minus 0.7 times age), which is more accurate than the old 220 minus age, and lets you enter a measured max if you have one. Whether you are building an aerobic base, programming intervals or guiding a return to running, the zones give you a clear target to train and monitor against.

HOW TO USE

1.  Enter the athlete's age.

2.  Enter their resting heart rate.

3.  Choose a method: percentage of max HR, or Karvonen.

4.  Read the five zones in bpm, and enter a measured max HR to override the estimate if you have one.

 WHAT YOU GET

A max HR estimate, heart rate reserve, and the five training zones (Recovery, Aerobic base, Tempo, Threshold, VO2 max) in bpm.

WHO IT IS FOR

Physios, S&C coaches, runners, and anyone prescribing or monitoring aerobic training.