One-Rep Max Calculator
Estimate your 1RM from any hard set, then get a full percentage-of-1RM training-load chart.
Your result
Enter a set on the left to estimate your one-rep max and a full percentage-of-1RM training table.
Programme to your real numbers.
Misi BioLabs builds periodised four-week blocks, auto-calculates working loads from your logged lifts, and adjusts volume based on your daily readiness.
Frequently asked
How is one-rep max calculated?
A 1RM estimate uses the weight and reps of a hard submaximal set. This calculator averages four validated formulas — Epley, Brzycki, Lombardi and O’Conner — because no single equation is best for every person, and averaging reduces the error of any one of them.
How accurate is a 1RM estimate?
Estimates are most accurate at 1–6 reps and stay useful up to about 10. Above 10 reps, fatigue and endurance vary so much between people that the number drifts — re-test with a heavier set of 3–6 reps for a tighter figure.
What can I do with my 1RM?
Most strength programmes prescribe load as a percentage of 1RM — for example 5×5 at 80%, or speed work at 60%. The training table on this page converts your estimated 1RM into those working loads so you can programme without guessing.
Should I actually test a true 1RM?
Rarely. A genuine max attempt is fatiguing and carries injury risk, especially without a spotter and good technique. An estimate from a clean set of 3–6 reps gives you almost all the information with far less risk.