1RM Calculator - One Rep Max Calculator

Calculate your one rep maximum (1RM) using scientifically validated formulas. Enter any weight and rep combination to estimate your maximum lift for squat, bench press, deadlift, or any exercise.

Available 1RM Formulas

  • Epley Formula - Most widely used, best for 5-10 reps
  • Brzycki Formula - Conservative and accurate, ideal for 6-10 reps
  • Lander Formula - Well-balanced, good for 3-12 reps
  • O'Connor Formula - Safe and conservative, best for 5-15 reps
  • Lombardi Formula - Power function based, ideal for 8-15 reps

How to Calculate Your 1RM

Select your preferred formula, enter the weight you can lift and how many reps you performed. The calculator will estimate your one rep maximum using proven mathematical models.

1RM Calculator

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1RM Calculator

Calculate your one-rep maximum using proven formulas

Formula Selection

Choose your preferred 1RM calculation method

Selected: Epley (Default)
🎯 Most widely used 📊 Best: 5-10 reps 🏋️ Ideal: All exercises, powerlifting 👤 Users: Everyone

Calculate Your 1RM

Enter the weight and reps you can currently lift

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