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TOOLS · STRENGTH

One-Rep Max Calculator

Estimate your 1RM from a working set, no need to test a true max.

Estimated one-rep max

116.7 kg

Percentage chart

% of 1RMWeight
100%116.7 kg
95%110.8 kg
90%105 kg
85%99.2 kg
80%93.3 kg
75%87.5 kg
70%81.7 kg
65%75.8 kg
60%70 kg
55%64.2 kg
50%58.3 kg

How this calculator works

Each formula estimates your one-rep max from the weight and reps of a single working set, so you can track strength without grinding out a true max every few weeks. Epley and Lombardi tend to run slightly higher at low rep counts, Brzycki slightly lower above 10 reps. Pick one and stick with it so your progress line stays comparable week to week.

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