Free Tool
1RM Percentage Calculator | Training Load Calculator
Calculate percentage-based training loads from your 1RM. Get weight for any percentage.
Built by an engineer who chases finish lines and is obsessed with data. Thomas Prommer — technology executive who has worked with Google, Apple, Nike, Adidas, Netflix and other global brands. Also an Ironman finisher, HYROX Pro Division competitor, and marathon runner. These tools combine engineering rigor with real race experience.
1RM Percentage Calculator
Enter your known 1RM to get a complete percentage-based loading chart for training.
How to Use This Chart
Enter your known or estimated 1RM and set reps to 1. The chart shows training weights for each percentage. Use 85-100% for strength (1-5 reps), 65-80% for hypertrophy (6-12 reps), and 50-65% for endurance (12-20+ reps).
FAQ
What percentage for strength training?
85-100% of 1RM for 1-5 reps. This develops maximal strength and neural efficiency.
What percentage for hypertrophy?
65-80% of 1RM for 6-12 reps. This rep range maximizes muscle growth through mechanical tension and metabolic stress.
What percentage for endurance?
50-65% of 1RM for 12-20+ reps. Builds muscular endurance and work capacity.
How often should I retest my 1RM?
Every 4-8 weeks or at the end of a training cycle. You can also estimate from recent heavy sets.