Free triathlon tool
Heart Rate Zones Calculator
Calculate heart-rate training zones from LTHR or heart-rate reserve.
Inputs
Heart-rate zones
Zone 1 - Recovery
Easy recovery effort.
<143 bpm
Zone 2 - Endurance
Comfortable aerobic endurance.
145-151 bpm
Zone 3 - Tempo
Steady moderate work.
153-160 bpm
Zone 4 - Threshold
Hard sustainable effort near threshold.
162-168 bpm
Zone 5 - Above threshold
High intensity efforts above threshold.
170+ bpm