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Heart Rate Calculator — Free Online Calculator

Heart Rate solves Max HR ≈ 220 − age — the Fox formula estimate; actual max heart rate varies by individual and this is only a population-average estimate. Enter your known values and the calculator solves for the rest instantly. It runs entirely in your browser, so nothing you enter is uploaded to a server. Free to use, with no signup and no watermark.

How to use Heart Rate

1. Enter your known values in the fields.
2. The result updates instantly as you type.
3. Copy or note down the result.

Frequently asked questions

What formula does Heart Rate use?

Max HR ≈ 220 − age — the Fox formula estimate; actual max heart rate varies by individual and this is only a population-average estimate.

Can I use it on my phone?

Yes. The layout adapts to small screens and behaves the same on mobile as on desktop.

Is my input saved anywhere?

No. Values stay in your browser and are gone as soon as you close the tab.

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