one rep max

One Rep Max Calculator

How the 1RM calculator works

To use our 1RM calculator, follow these steps.

  1. Pick a weight that is a reasonable challenge for you.
  2. After a brief warm up, remembering to stretch, lift that weight as many times as you can.
  3. When you reach muscular failure (the point when your working muscle is fully fatigued to the extent that it can no longer complete another repetition of a movement), slowly lower the weight.
  4. Type the weight into the calculator, in the box that matches the number of reps you accomplished.
  5. Read your one rep max from the top.

Note: If using free-weights, you will need a spotter!

You’ll notice how much easier it is to use the bench press calculator, as opposed to just trying to lift a weight that you suppose is close to your max bench weight. Using a calculator eliminates the guesswork.

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