How to use this tool
Enter your values, run the tool, then review the result cards. Most tools update automatically when inputs change, so you can test several scenarios quickly.
Example inputs
- Age: 30
- Resting heart rate: 60
Results this page provides
- Max heart rate
- Zone 2 low
- Zone 2 high
- Zone 4 high
How it works
Uses the Karvonen method with estimated max heart rate and resting heart rate.
Best use cases
Plan cardio sessions and compare wearable readings.
Limitations
Estimated zones may differ from lab-tested thresholds.