One Rep Max Calculator

Calculate your one-rep max for any lift based on a submaximal effort.

Your Lift Data

Unit

Weight Lifted

lbs

The weight you lifted

Repetitions

reps

Number of reps completed (max 30)

Quick Rep Buttons

About 1RM

This calculator uses the Brzycki formula to estimate your one-rep max:

1RM = Weight × (36 / (37 - Reps))

The estimate is most accurate for rep ranges of 1-10. Higher rep ranges become less accurate.

Related Calculators

Calculate your Basal Metabolic Rate - the calories your body burns at rest.

Calculate your Total Daily Energy Expenditure - total calories burned per day.

Estimate calories burned during exercise based on activity type and duration.

Your One Rep Max

Estimated 1RM

Training Percentages

100% (1 rep)208.13 lbs

95% (3 reps)197.72 lbs

90% (3 reps)187.31 lbs

85% (6 reps)176.91 lbs

80% (6 reps)166.5 lbs

75% (10 reps)156.09 lbs

70% (10 reps)145.69 lbs

65% (15 reps)135.28 lbs

60% (15 reps)124.88 lbs