One Rep Max Calculator
Calculate your one-repetition maximum using proven formulas. Get personalized training load recommendations and rep range charts for optimal strength development.
Ready to Calculate
Enter your lift details and click "Calculate 1RM" to get your estimated one-rep maximum and training recommendations.
1RM Calculator Guide
Your one-rep maximum (1RM) is the heaviest weight you can lift once with proper form. Use it to design training programs, track progress, and train at the right intensity for your goals.
Which Formula to Use
Brzycki: Best for 1-7 reps (most accurate for powerlifting)
Epley: Best for 8-15 reps (most commonly used)
O'Conner: Good middle ground for 5-10 reps
Lombardi: Conservative estimates (good for beginners)
Important: These are estimates that can vary ±5-10%. Calculate when fresh, use proper form, and test actual 1RMs progressively with spotters. Results are specific to each exercise.