One Rep Max Calculator

Estimate your one-rep max (1RM) from a lifted weight and reps.

Estimated 1RM93.333333 kg
95%88.666667 kg
90%84 kg
85%79.333333 kg
80%74.666667 kg
75%70 kg
70%65.333333 kg

For general information only. Not medical advice — consult a professional.

How to use

Enter your values above and read the result instantly.

How it works

Everything is computed locally in your browser — nothing is uploaded.

Frequently asked questions

Is it free?

Yes, completely free with no limits.

Is my data private?

Yes, all processing happens in your browser.

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