CalcArena

Epley One-Rep Max Calculator

Predict your one-repetition maximum from a challenging submax set using the trusted Epley formula.

Enter Your Lift

Best results come from tough sets of 3 to 10 reps with solid form.

Results

Estimated One-Rep Max --

70 percent 1RM

--

80 percent 1RM

--

90 percent 1RM

--

How the Epley Formula Works

Formula

1RM = weight x (1 + reps / 30)

Step-by-step

  1. Perform a submaximal set for 3 to 10 reps using controlled technique.
  2. Multiply the completed rep count by 1/30 (about 0.0333) and add 1.
  3. Multiply the weight lifted by that factor to estimate your one-rep max.

Notes

The Epley formula is reliable for low to moderate rep ranges (10 or fewer). Using higher reps may overestimate your true maximum due to endurance factors.

References