Fitness

One Rep Max Calculator

Estimate your one-repetition maximum (1RM) from sub-maximal lift data using 7 formulas.

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One Rep Max Calculator

— kg 1-REP MAX
Estimated 1-Rep Max
kg
Training Percentage Table
%Weight (kg)Reps (approx)

What Is One Rep Max?

One Rep Max (1RM) is the maximum weight you can lift for one complete repetition of an exercise with proper form. It is used to measure absolute strength and to set training loads as percentages of 1RM.

Common Formulas

Epley: 1RM = w × (1 + r/30)

Brzycki: 1RM = w × 36 / (37 − r)

Lombardi: 1RM = w × r^0.1