One-rep max calculator
Estimate the heaviest weight you could lift for one rep, from a set you've actually done.
Estimated 1RM
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90%
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80%
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70%
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60%
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Training percentages are handy for programming: most strength programs cycle through 60–90% of your 1RM across a training block.
How this is calculated
This uses the Epley formula — 1RM = weight × (1 + reps ÷ 30) — one of the most widely used estimates for squat, bench, and deadlift. It works for any lift, but gets less reliable past about 10–12 reps.
This is a mathematical estimate, not a tested max. Always use a spotter and proper form when attempting new personal records.
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