💪 One-Rep Max Estimator
Estimate your 1-rep max from any lift
About this calculator
Your one-rep max is the heaviest weight you can lift for a single repetition, and it is the number every strength program is built around. Instead of risking injury by testing it directly, you can estimate it from a lighter set taken close to failure. This calculator uses the Epley formula, the most widely used estimate, and shows the Brzycki formula as a cross-check plus your training percentages.
Tip: Estimates are most accurate from sets of 3 to 8 reps. A 12-rep estimate is a guess, not a number to plan around.