1 Rep Max Calculator

Calculator

This One Rep Max (1RM) calculator can help you estimate your maximum strength for any lift across various rep ranges. It also calculates the percentages of your 1 rep max required by many training programs. Any lift can be used from olympic lifts like Bench Press, Squat, and Deadlift to isolation lifts like bicep curls. This calculator uses many well known formulas to calculate these estimates. Here's how to use it:

1. Start by warming up and then performing the lift you'd like to calculate in a rep range you're comfortable with. Generally lower rep ranges (less than 8) yield more accurate estimates. Do as many reps as you can with good form.
2. Enter the weight you lifted and the number of reps you accomplished in the input fields.
3. Your 1 rep max is the first value displayed in the table. That is the estimate for the maximum weight you can lift for a single repetition. The 2 Rep Max row shows the estimated maximum weight you can lift for 2 repetitions and so on.

Plate Loader

Now that you know what weight you can lift, let's load up the bar! Expand any row to reveal the plate loader. This shows a visualization of what plates to load on each side of the bar.

Is the loader showing a plate you don't have? No problem, pick your available plates on the Settings page.

The plate loader shows the difference between the estimated max and the visualized barbell. You can adjust the weight on the barbell using the +/- buttons. Go ahead and try below, it's interactive!

Formulas

The calculator uses 7 formulas to calculate these estimates: Brzycki, Epley, Lander, Lombardi, Mayhew et al., O'Connor et al., and Wathan. These estimates are averaged together to give the final estimate displayed.

What do the colors mean? Since each formula produces a different value, the colors represent how much uncertainty there is in the final value. The standard deviation of the formulas is used to determine the color. The lower the standard deviation, the more agreement there is between the formulas.

• Green: 2% or less

• Orange: 2%-4%

• Red: Over 4%