Target Heart Rate Calculator

What this Target Heart Rate Calculator calculates

Target heart-rate zones are commonly estimated in two different ways. Percent-of-maximum uses a percentage of estimated maximum heart rate directly. The Karvonen method first calculates heart-rate reserve by subtracting resting heart rate from estimated maximum and then adds resting heart rate back after applying the intensity percentage. This calculator supports both approaches and lets you compare two maximum-heart-rate formulas.

The result is intentionally more than a single number. Supporting figures are shown beside the headline answer so you can see which part of the calculation is driving the outcome. This makes the tool useful for scenario testing: change one assumption, calculate again, and compare the supporting values rather than relying on a black-box result.

Formula and calculation method

Karvonen: (estimated max HR − resting HR) × intensity + resting HR. Percent-max: estimated max HR × intensity.

Inputs are validated before calculation and the arithmetic runs locally in the browser. Monetary fields use the selected currency only for display formatting. The calculator does not retrieve bank, payroll, property, medical, market or exchange-rate data from an external service.

How to use it

1. Enter values that describe the same scenario and reporting period.
2. Keep percentages and units consistent with the labels shown beside each input.
3. Select Calculate and review both the headline result and the supporting metrics.
4. Change one assumption at a time to understand sensitivity instead of accepting a single scenario.
5. Use Copy Result, Share Result or Save Result Image when you need to keep a record of the calculation.

Worked example

How to interpret the result

Estimated heart-rate zones are general training references. Perceived exertion, talk test, pace, power, recovery and sport-specific guidance can also be useful. Maximum heart rate can differ substantially between individuals of the same age, so a measured value from an appropriate supervised test may differ from either age-based formula.

For an important decision, compare the output with original documents, lender or employer terms, supplier information, professional guidance, or other authoritative records relevant to the calculation. Small differences in rates, timing, fees and definitions can materially change a result even when the formula itself is correct.

Important assumptions and limitations

This calculator is for general informational use and is not medical advice. Medications, cardiovascular conditions, heat, altitude, dehydration, illness, pregnancy and fitness status can affect heart-rate response. People with medical concerns or exercise restrictions should follow guidance from an appropriate healthcare professional rather than relying on an age formula.

This calculator is for planning, checking, education and general informational use. It is designed to make assumptions visible and calculations reproducible, but it does not replace a contract, disclosure, professional opinion, medical assessment, accounting policy or lending decision.

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