Calculate your one-rep max (1RM). Our calculator helps you estimate your 1RM easily.
This calculator lets you enter the weight and number of repetitions you can perform in a strength exercise to estimate the maximum weight you can lift for one rep. For instance, if you bench press 225 lbs for 5 reps, the estimated 1RM would be 253.2 lbs.
There are several formulas used to estimate 1RM, but one of the most popular and fairly accurate methods is Matt Brzycki’s formula.
Formula for 1RM:
$$\frac{weight ~ in ~ lbs ~ or ~ kgs}{1.0278 – (0.0278 \times repetitions)}$$
Estimated 1RM: