1-Rep Max Estimator

Estimate your one-rep max (1RM) from a submaximal lift. Enter the weight you lifted and the number of reps you completed, and get results from three proven formulas — Epley, Brzycki, and Lombardi — plus a percentage chart and warm-up pyramid.

Units
Weight unit
Weight Lifted
lbs
Reps Performed
reps
Exercise (optional)
How are the formulas calculated?

Three widely-used formulas estimate your 1RM from submaximal data. Each works best in slightly different rep ranges, so we average all three for a more reliable estimate.

Epley (1985):

1RM = weight × (1 + reps / 30)

Brzycki (1993):

1RM = weight × 36 / (37 − reps)

Lombardi (1989):

1RM = weight × reps0.10

These formulas are most accurate in the 2–10 rep range. At very high rep counts (15+) accuracy decreases. If you enter 1 rep, the weight you lifted is your 1RM.

Tip: Use your most recent set where you reached technical failure or near-failure for the most accurate estimate.