One Rep Max Calculator

Calculate your one-rep max (1RM) for any lift. Your one-rep max is the maximum weight you can lift for a single repetition for a given exercise.

The number of repetitions performed at the above weight

Repetition Percentages of 1RM

RepetitionsPercentage of 1RM
1100%
297%
394%
492%
589%
686%
783%
881%
978%
1075%
1173%
1271%
1370%
1468%
1567%
1665%
1764%
1863%
1961%
2060%
2159%
2258%
2357%
2456%
2555%
2654%
2753%
2852%
2951%
3050%

The above one rep max calculator is calculated using the Brzycki formula – created by Matt Brzycki. There are many different formulas but the Brzycki formula is the most common and most proven accurate.