Heart Rate Zone Calculator
Know which pulse is easy, tempo or hard for you.
The Karvonen method uses your heart rate reserve (max minus resting), which fits individual fitness better than plain percentages of max. Leave max empty to estimate it as 220 minus age.
Formula: Zone limit = rest + percentage × (max − rest)
Results are estimates for general information, not medical or financial advice.
How it works
- Enter your values The result updates as you type.
- Switch units if needed Metric or US units, where it applies.
- Read the result Nothing is stored or sent anywhere.
FAQ
Is it free?
Yes. No account, no limits.
Is my data stored?
No. The calculation happens in your browser and nothing is sent to a server.