Sports & Fitness tool

One-Rep Max Calculator

Estimate maximum strength from a lifted weight and repetition count.

How to use One-Rep Max Calculator

One-rep max, or 1RM, is the estimated maximum weight you can lift for one repetition with good form.

Basic idea

Weight lifted + repetitions = estimated 1RM

Is estimated 1RM exact?

No. It is an estimate and becomes less accurate when the set uses many repetitions.

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