One-rep max calculator: estimate from a completed set

Use a familiar exercise, a known load and a completed set of one to ten repetitions to explore an Epley estimate. You do not need to attempt a maximum lift.

Enter the set you actually completed

Use the external load for one exercise and keep the units consistent. Choose kilograms or pounds, then enter whole repetitions from one to ten. The result stays in your selected unit. This form does not assess technique, assistance, fatigue or how close the set was to failure.

The Epley calculation

For two to ten repetitions, estimated one-repetition maximum = load × (1 + repetitions ÷ 30). A set of 60 kg for five repetitions gives 60 × 1.1667 = about 70 kg. For a single completed repetition, the tool returns the entered load rather than increasing it. This special case avoids suggesting that a known single automatically proves a higher maximum.

What makes the estimate uncertain

Repetition-based formulas are approximations, and accuracy depends on the exercise, person, load and set conditions. A comfortable set stopped early is not the same input as a controlled near-maximal repetition test. Do not compare different exercises as though they share the same strength measure. The 10-repetition limit narrows the tool scope; it does not guarantee accuracy.

Use the result as a record, not a challenge

A number on a page is not a reason to load the bar to that amount. Heavy testing requires appropriate technique, equipment, supervision and individual readiness. Stop for pain or concerning symptoms. For ordinary routine planning, use comfortable loads and qualified coaching when you need help with technique.

Why does the one-repetition result equal my load?

You have reported one completed repetition. Returning that load makes the interpretation clear. For multiple repetitions, the Epley formula extrapolates beyond the set; the displayed value is rounded to one decimal and should not be mistaken for a tested maximum.

Sources and related tools

For research on repetition-based prediction accuracy, see LeSuer et al., The accuracy of prediction equations for estimating 1-RM performance. WHO physical activity guidance provides public-health context. It does not validate an individual exercise plan. Organize comfortable sessions in the workout planner.

Editorial information

Prepared with AI assistance for Everyday Wellness Planner. Last checked: 9 October 2026. No independent clinical review is claimed. Read our editorial policy and educational disclaimer. Calculator inputs remain in this browser tab; ordinary site logs and analytics are described in the privacy notice.

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