One Rep Max Calculator
Calculate your one-rep maximum for strength training and powerlifting using proven formulas.
Calculate Your 1RM
Enter the weight lifted and reps performed.
Most commonly used, good for 2-10 reps
Unit
Important Safety Notes
• Always warm up properly before attempting heavy lifts.
• Use a spotter when attempting near-maximum weights.
• These are estimates - actual 1RM may vary based on training, fatigue, and technique.
• Do not attempt a true 1RM more than once every 4-6 weeks.
• Consider using these estimates for programming rather than testing your actual 1RM.