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One-Rep Max Calculator

Estimate your 1RM from a lifted weight. Everything happens locally in your browser, so it is fast and completely private. Nothing you enter is uploaded.

Free · no sign-up Health

About the One-Rep Max Calculator

Estimate your 1RM from a lifted weight. Everything happens locally in your browser, so it is fast and completely private. Nothing you enter is uploaded.

Frequently asked questions

Is this tool free?
Yes — it is completely free, with no sign-up or watermark.
Is my data private?
Yes. It runs entirely in your browser, so nothing you paste or upload ever leaves your device.

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