One Rep Max Calculator Calculate your One Max Rep instantly. What's Your Score? Fill out your information for an instant calculation of your One Rep Max. Weight Lifted Units - Select -lbskgsReps Performed Your One Rep Max is Percentage of 1RM Lift Weight Repetitions of 1RM 100% 1 95% 2 90% 4 85% 6 80% 8 75% 10 70% 12 65% 16 60% 20 55% 24 50% 30 100 Percentile 95 Percentile 90 Percentile 85 Percentile 80 Percentile 75 Percentile 70 Percentile 65 Percentile 60 Percentile 55 Percentile 50 Percentile Submit Form