One Rep Max Calculator

Free one rep max calculator: enter a weight and reps to estimate your 1RM using the Epley and Brzycki formulas. A training estimate only. 100% Local

Inputs

Weight lifted (kg)

Repetitions (1–30)

Result

How to Use the One Rep Max Calculator

Enter the weight you lifted and the number of repetitions, then press Estimate 1RM. The result updates as you type.

How it works

The Epley and Brzycki formulas each estimate a one-rep maximum.
Both are most accurate at low to moderate rep counts.
An average of the two is shown for a single reference figure.

Features

Epley and Brzycki 1RM estimates
Average of the two formulas
Rounded kilogram results
All processing runs locally in your browser. Your data is not uploaded to any server.
This is a training estimate, not medical or coaching advice.

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