Updated
Using One rep max calculator
Estimate a one-repetition maximum with the Brzycki equation: load / (1.0278 - 0.0278 x repetitions).
Use 1 to 10 completed repetitions with the same unit throughout. This is an estimate from a submaximal set, not a safe load to attempt or a strength standard. Accuracy depends on the exercise, technique, fatigue and training history. The equation cannot validate a bench press, squat or deadlift technique.
A worked example
For load lifted (kg or lb) = 100, completed repetitions = 5, estimated one-rep maximum (same load unit) = 112.511251.
Before you use the result
Use 1 to 10 completed repetitions with the same unit throughout. This is an estimate from a submaximal set, not a safe load to attempt or a strength standard. Accuracy depends on the exercise, technique, fatigue and training history. The equation cannot validate a bench press, squat or deadlift technique.
Example results for load lifted (kg or lb)
These examples use Completed repetitions: 5. They are reference calculations, not recommended settings.
| Load lifted (kg or lb) | Estimated one-rep maximum (same load unit) |
|---|---|
| 50 | 56.255626 |
| 100 | 112.511251 |
| 200 | 225.022502 |
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ToolOctopus. “One rep max calculator.” Updated 2026-09-29. https://tooloctopus.com/one-rep-max-calculator.
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