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Fitness
Karvonen Heart Rate Zones
Calculate target heart-rate zones from max and resting heart rate.
Updated: May 15, 2026
Input
Calculate heart-rate-reserve zones from max and resting heart rate.
Not medical advice. Medical conditions, medication, heat, and current condition can change safe ranges.
Result
130 bpm
Heart-rate reserve
Zone 1
50-60% HRR / 125-138 bpm
Zone 2
60-70% HRR / 138-151 bpm
Zone 3
70-80% HRR / 151-164 bpm
Zone 4
80-90% HRR / 164-177 bpm
Zone 5
90-100% HRR / 177-190 bpm
Use this as a guide and adjust for your real conditions.
Share this tool
How to use
- Enter Max heart rate, Resting heart rate.
- Check the estimate in the result area.
- Share a reproducible URL if needed.
How to read the result
- Read Target zones, Heart-rate reserve as quick decision-making estimates.
- Do not treat the result as a fixed answer; adjust assumptions to see the range when needed.
Useful tips
- Useful when you want to set heart-rate training ranges; adjust inputs to compare scenarios.
- Useful when you want to use resting heart rate in zone estimates; adjust inputs to compare scenarios.
- Use results as training guides and adjust for condition, heat, surface, and fatigue.
- If the result feels too demanding, reduce distance, intensity, or duration and recalculate.
Calculation
Calculates heart-rate reserve from max and resting heart rate, then shows Karvonen target zones.
Notes
- Adjust for your condition and environment.
- This is not medical or coaching advice.
- Stop exercising if you feel pain or discomfort.
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FAQ
Are results exact?
Use results as everyday estimates. For exact decisions, confirm with official or specialized sources.
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