Method
Uses the Epley estimate: weight × (1 + reps ÷ 30).
Health / browser tool
One Rep Max Calculator
Estimate one-repetition maximum from a submaximal lift.
Use an Epley estimate from a weight and repetition count.
Your inputs stay on your device
Estimate one-rep max
live resultEstimated one-rep max
Epley estimate: weight × (1 + reps ÷ 30)
Fitness reference only, not medical guidance. Stop if you feel pain or unwell and use qualified coaching for exercise programming.
Context & Reference
How it works
For estimating a one-repetition maximum from a submaximal set.
calculator guideHow to use it
Use this calculator with your own values, then review the clearly labelled result and copy it when you need it elsewhere.
Understand the result
The result is an approximate strength estimate in the input weight unit.
Example
Estimate 1RM from 80 kg for 8 repetitions.
Practical tip
Do not attempt a maximal lift based only on this estimate.
Notes
This calculator runs locally in this browser. Do not attempt a maximal lift based only on this estimate.
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