3RM (3-Rep Max) Calculator

Author: Calculator Academy Team

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Enter the total weight you lifted and the number of reps into the calculator to determine your estimated 3 rep max.

3 Rep Max Calculator

Basic Calculator
Advanced Calculator

Enter any 2 values to calculate the missing variables

3RM Formula

The following formula is used to calculate a 3 repetition maximum weight.

3RM = 1RM*.93
  • Where 3RM is your 3 rep max
  • 1RM is your 1 rep max

To calculate your three rep max (3RM), multiply your 1 rep max by .93.

3RM Definitoin

What is 3RM?

3RM is a term used in the fitness world to describe the maximum amount a person can lift 3 times. In other words, the person’s three rep max.

How much is my 3 rep max?

A 3 rep max is estimated to be around 93% of the weight of your one-rep max. This will vary slightly depending on the exercise, but in general, the average is 93% of 1 rep max.

Example Problem

How to calculate 3rm?

  1. First, perform an exercise to failure and note the weight and reps.

    For this example, a person is lifting a bench press of 225lbs and manages 8 reps until they hit failure.

  2. Next, determine the estimated max lift.

    Using the calculator linked above, the max lift of this bench press is estimated to be 272.25 lbs.

  3. Finally, calculate the 3-rep max.

    Using the formula above, the 3 rep max is calculated to be:
    3RM = 1RM*.93
    3RM = 272.25 *.93
    3RM = 253 .19 lbs.

3rm calculator