Summary
Epley and Brzycki one-rep-max estimates from a working set.
Calculation details
Estimates are less reliable above about 10–12 repetitions and are not a substitute for careful testing.
Formula
Epley: w(1 + reps/30); Brzycki: w × 36/(37 − reps).
Worked example
One-rep max worked example
Both formulas estimate a higher one-rep maximum than the working weight.
How it works
Enter a working weight and completed repetitions. Compare both formulas; estimates degrade above roughly 10–12 reps.
Frequently asked questions
Is this a medical diagnosis?
No. It is an educational estimate and cannot diagnose a condition or replace individualized professional advice.
Why can my actual result differ?
Formula estimates diverge and become less reliable above about 10–12 repetitions.
When is this calculator most useful?
Use it to compare Epley and Brzycki estimates from a working set — not as a substitute for careful testing.
How are results rounded?
The calculation retains full precision; centralized display formatting rounds only the visible result.