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1RM Calculator — estimate your one-rep max
Estimate a training reference from the load and reps you have already completed.
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What is a one-rep max?
The heaviest load you could lift for one complete repetition with good technique.
How is it estimated?
With the Epley formula: load × (1 + reps ÷ 30). Estimates are most dependable from sets of about ten reps or fewer, so this calculator accepts up to twelve.
Do I need to test my true max?
Most people do not. An estimate is a safer way to set training loads; if you do test, use a spotter and stop any rep your technique can't support.