Target Heart Rate Zones
Calculate personalized training zones. Uses Karvonen (heart rate reserve) when resting HR is provided, else simple % of max. Updates live.
Your zones
Very Light
Warm-up / Recovery
124–136 bpm
Light
Fat Burn / Aerobic
136–148 bpm
Moderate
Cardio / Endurance
148–160 bpm
Hard
Threshold / Tempo
160–173 bpm
Peak
VO2 Max / Sprints
173–185 bpm
Max heart rate (220−age)
185 bpm
Heart rate reserve
123 bpm
Method in use
Karvonen (HR reserve)
Runs locally. No sign-up. These are estimates — consult a doctor or coach for personalized zones.