Health & fitness · NUMORA
One Rep Max Calculator
Epley: 1RM = w × (1 + reps/30).
Open interactive calculatorHow to use
High-rep estimates are noisier.
Formula
1RM = w (1 + r/30)
FAQ
Is this One Rep Max calculator accurate?
The formula and assumptions are shown on the page, and the engine is covered by audit tests. Results are for reference — not financial or medical advice.
Do I need an account?
No. Calculations run in your browser. Recents can stay on this device.
What inputs do I need?
High-rep estimates are noisier.
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