One-Rep Max Calculator
Estimate one-repetition maximum from lifted weight and reps using Epley, Brzycki and other established formulas.
Enter or adjust the values above, then calculate.
One-Rep Max: epley, Brzycki & More
Estimate one-repetition maximum from lifted weight and reps using Epley, Brzycki and other established formulas.
Inputs this tool uses
- Weight lifted
- Repetitions
- Formula
What you get
Estimated one-repetition maximum.
How to use the One-Rep Max Calculator
- Enter weight lifted, repetitions, formula.
- Select any method, activity level or option shown on this page, then choose Calculate.
- Read the main result together with the supporting values, method, assumptions and limitations below before using the estimate.
How this calculation works
One-rep max estimates use established formulas such as Epley and Brzycki; higher-repetition sets reduce confidence.
Example calculation
The sample values loaded into the calculator produce 91.7 kg. This example exists to show how the output is structured; replace the sample values with your own inputs for your calculation.
Assumptions and limitations
- Energy, fitness and heart-rate outputs are estimates and vary by individual and device.
- Stop exercise and seek appropriate care if you have concerning symptoms; this tool does not provide medical clearance.
Sources and review status
Source set last verified 2026-09-25. No clinician review is claimed unless a real named reviewer is displayed.
Questions people ask about One-Rep Max Calculator
Should I test the estimated one-rep max in the gym?
Not necessarily. The result is an estimate from a submaximal set. Higher-repetition sets are less reliable, and lifting safety matters more than matching the predicted number.
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