One Rep Max Calculator
Estimate 1RM from lifted weight and repetitions using the Epley formula.
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What This Calculator Does
Estimate 1RM from lifted weight and repetitions using the Epley formula.
It combines Lifted Weight, Repetitions to estimate Estimated 1RM, Estimated 5RM, Estimated 10RM.
Formula & Method
Core equations: Epley 1RM: 1RM=W(1+r/30). Optional compare with Brzycki: 1RM=\frac{36W}{37-r}.
Notation used in the formulas: R = Estimated 1RM; x_{1} = Lifted Weight; x_{2} = Repetitions.
Method summary: inputs are normalized to consistent units, core equations are evaluated, then secondary values are derived and rounded for display.
Use this calculator for quick scenario analysis. Start with baseline values, change one driver at a time, and compare how sensitive the results are to each input shown above.
Inputs Used
- Lifted Weight: Used directly in the calculation.
- Repetitions: Used directly in the calculation.
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