How accurate is the Epley formula?

The Epley formula is most accurate for 2-10 rep sets. Error increases for higher rep sets above 12. It tends to slightly overestimate 1RM for trained lifters.

Should I actually lift my calculated 1RM?

Only attempt a true 1RM with proper supervision, thorough warm-up, and spotter. The formula provides a safe estimate for programming percentages without the injury risk of maximal testing.

Which 1RM formula is most accurate?

No single formula is universally best. Brzycki is preferred for low rep sets, Epley for moderate sets. Average multiple formulas for better accuracy.

1-Rep Max Epley Formula Calculator

Estimate 1 rep max using the Epley formula: 1RM = weight x (1 + reps/30). Most accurate for sets of 2-10 reps.

Use the full interactive calculator below, or

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1-Rep Max Epley Formula Calculator

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Frequently Asked Questions

How accurate is the Epley formula?

Should I actually lift my calculated 1RM?

Which 1RM formula is most accurate?