Heart Rate Calculator
Your entries are calculated in this browser and are not saved by this tool.
This result is an estimate and does not diagnose, prevent or treat any condition. Consult a qualified health professional.
How the Heart Rate Calculator works
Estimate a training heart-rate range with the Karvonen heart-rate-reserve method. Enter the requested values in the tool above, select Calculate, and review both the main result and its breakdown.
Formula used
Maximum heart rate estimate = 208 − 0.7×age. Target = resting HR + intensity × (max HR − resting HR).
Worked example
At age 40 with resting HR 60, 70% heart-rate reserve is about 144 bpm.
Practical uses
- Estimate a training zone
- Compare intensity levels
- Discuss exercise limits with a clinician
Assumptions and limits
Health results are screening estimates, not a diagnosis. Individual needs and clinical circumstances can differ. For reproducibility, record the inputs and assumptions used when sharing a result.
Frequently asked questions
Is this calculator free?
Yes. It can be used without creating an account.
Are the values I enter stored?
The calculation runs in your browser. The core tool does not submit your calculator entries to WordPress.
Can I rely on the result for a major decision?
Use it as an educational estimate, verify important inputs, and seek qualified advice when the decision carries financial, medical, tax or legal consequences.