How it works
This page uses the Epley equation to estimate one-repetition maximum from a submaximal set. It is a training estimate, not a requirement to attempt a maximal lift.
Standard formula
weight × (1 + repetitions / 30)Worked example
Lifting 100 kg for 5 repetitions gives an estimated 1RM of 116.67 kg with the Epley formula.
Frequently Asked Questions
What does 1RM mean?
It means the heaviest load you could lift once with proper form for a specific exercise.
Is the result exact?
No. It is an equation-based estimate and should guide training rather than replace testing.
How many repetitions should I enter?
The Epley estimate is commonly used for sets of 1 to 10 repetitions; this tool accepts up to 20.
Does it work for every exercise?
It can be a rough estimate, but exercises and athletes differ in how well the formula predicts performance.