One Rep Max Calculator
Estimate one-rep max using Epley and Brzycki strength formulas.
Tool-specific inputs
These inputs aren't part of the dashboard. Adjust them to refine the result above.
How this works
Uses Epley (weight x (1 + reps / 30)) and Brzycki (weight x 36 / (37 - reps)) one-rep max formulas.
Medical disclaimer
Educational tool only — not medical advice. Consult a qualified provider.
Frequently asked questions
What does the One Rep Max Calculator estimate?+
It estimates estimated maximum lift from lifted weight and repetitions. The result is a planning estimate, not a diagnosis or personal medical advice.
How accurate is this one rep max result?+
Accuracy depends on the inputs and the limits of the formula. Use the result as a reference point and compare it with real-world outcomes over time.
Can I share my result?+
Yes. Change the inputs, use the copy-link button, and the current values are preserved in the URL for reopening or sharing.
Will my last input be remembered?+
Yes. The calculator saves the latest inputs in this browser so a reload can restore the most recent values.
Should I use this for medical decisions?+
No. These calculators are educational tools. Talk with a qualified clinician before making health, pregnancy, nutrition, or training decisions.