One Rep Max Calculator
Estimate your one rep max from any set of up to 12 reps using the Epley, Brzycki and Lombardi formulas, with a percentage training table.
Runs on your device
Result
Results appear here as you type.
What it does
Testing a true one rep max is risky. Estimating it from a heavy set lets you plan training percentages safely.
How to use it
- Enter the weight lifted and reps completed.
- Read the estimated 1RM.
- Use the percentage table to plan sets.
Example
100 × 5 gives an estimated 1RM of about 115. Select Try an example above to see it.
When it helps
- Programming strength training.
- Tracking progress safely.
- Choosing working weights.
Questions
Which formula is most accurate?
They agree closely for 3 to 6 reps. The average of the three is shown.
Kilograms or pounds?
Either; results are in the same unit you enter.
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