Free Tool
One Rep Max (1RM) Calculator
Calculate your one-repetition maximum and get a complete training percentage chart for all strength zones.
One Rep Max (1RM) Calculator
Enter weight and reps to calculate your 1RM
What is One Rep Max?
One Rep Max (1RM) is the maximum weight you can lift for a single repetition with proper form. It's calculated using the Epley formula: 1RM = Weight × (1 + Reps/30). Knowing your 1RM helps you program training at the right intensity for strength, hypertrophy, or endurance goals.