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= NumberOneCalc

One Rep Max Calculator

Estimated one-rep max from a lifted weight and rep count, plus a training load table.

kg

Your result appears here

Fill in the fields on the left and press Calculate. The answer, the breakdown and a copy button all land in this card.

How it is calculated

1RM = weight × (1 + reps ÷ 30)

The Epley formula is most accurate under about 10 reps — high-rep sets tend to overestimate the true one-rep max.

Worked example

60 kg for 8 reps estimates a one-rep max of 76 kg.

Questions people ask

Treat it as a training estimate, not a target to load and attempt cold. Real max attempts need a proper warm-up and, ideally, a spotter.

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