One Rep Max Calculator
Free 1RM calculator. Estimate your one rep max for any lift using multiple formulas.
Multiple Formulas
Calculates using Epley, Brzycki, and Lombardi formulas.
Percentage Chart
See weights for 50-100% of your 1RM.
Any Lift
Works for bench press, squat, deadlift, and any exercise.
FAQ
What is a 1RM?
One Rep Max (1RM) is the maximum weight you can lift for a single repetition with proper form.
How accurate are 1RM estimates?
Most accurate with 3-6 reps. Above 10 reps, estimates become less reliable. Error margin is typically 5-10%.