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

3RM Formula

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

3RM = 1RM*.93

  • Where 3RM is your 3 red max
  • 1RM is your 1 rep max

The calculator above first estimates your one-rep max using the weight and reps you enter, then it calculates the 3 rep max.

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.