One Rep Max (1RM) Calculator

Estimate your one rep max for any lift based on weight and reps performed. Includes training percentage chart.
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Input weight and reps to estimate your 1RM

About 1RM Estimation

The Epley formula is the most commonly used 1RM estimator: 1RM = weight × (1 + reps/30). These formulas are most accurate for 1-10 reps. Beyond 10 reps, accuracy decreases due to endurance factors.

Always warm up properly and use a spotter when attempting a true 1RM. The estimated value is a safe starting point for programming.

One Rep Max (1RM) Calculator - Free | CalcCentral