One Rep Max Calculator - Free 1RM Calculator

Calculate your one-repetition maximum (1RM) for any lift including bench press, squat, deadlift, and more. Estimate maximum strength based on weight and reps using proven formulas (Epley, Brzycki, Lander). Get personalized training zones for power, strength, hypertrophy, and endurance.

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Updated January 2025
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One Rep Max Calculator

Calculate your maximum strength and training zones

What is One Rep Max (1RM)?

Your 1RM is the maximum weight you can lift for one complete repetition. This calculator estimates your 1RM based on a weight you can lift for multiple reps, helping you plan training programs safely.

Enter 1-20 reps for accurate results

These calculations are estimates based on submaximal lifts. For accurate 1RM testing, work with a qualified coach or trainer. Always prioritize proper form and safety over heavy weights.