Heart Rate Zone Calculator
Calculate your 5 heart rate training zones using the Karvonen method (heart rate reserve).
Measure first thing in the morning for accuracy
Your Heart Rate Zones
Zone 1: Recovery
50-60% HRRVery easy effort, active recovery walks and easy jogs
Zone 2: Aerobic / Easy
60-70% HRRConversational pace, the bulk of your training should be here
Zone 3: Tempo
70-80% HRRComfortably hard, marathon to half marathon effort
Zone 4: Threshold
80-90% HRRHard effort, 10K to 5K race intensity
Zone 5: VO2max / Speed
90-100% HRRMaximum effort, interval and sprint training
About Heart Rate Training
The Karvonen method uses heart rate reserve (HRR = max HR − resting HR) to calculate zones. This is more accurate than simple % of max HR because it accounts for your individual fitness level via resting heart rate.
If you don't know your max HR, the Tanaka formula (208 − 0.7 × age) is the most widely validated estimate. A true max HR test is more accurate but requires maximal effort.
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