doomath Calculator
One-Rep Max Calculator
Estimate one-repetition maximum from a weight and repetitions using the Epley equation.
InputsChange a value to recalculate instantly
ResultUpdates as you type
How it worksTransparent math
Calculation details are shown above.
Result breakdownSee the important numbers together
1Estimated 1RM101.33 kg
2FormulaEpley
3Input set80 kg × 8 reps
λ DooMathWork with this calculation
Local · deterministic · optionalQuick mathNatural-language-style shortcuts for deterministic arithmetic.
Calculator guide
How to use the One-Rep Max Calculator
Estimate one-repetition maximum from a weight and repetitions using the Epley equation.
01Set inputsChoose values, units and assumptions.
02Apply the modelUse the stated mathematical relationship.
03Read the resultCheck the output against the assumptions before using it.
What this calculator does
Estimate one-repetition maximum from a weight and repetitions using the Epley equation.
Formula & method
The result is calculated from the inputs and assumptions shown in the calculator.
Assumptions & notes
Review the inputs, units and assumptions before using the result for a real decision.