# The One Rep Max Calculator Helps You Find Your 1RM Quickly

You don't want to use one of the several formulas to calculate your 1RM? The One Rep Max Calculator simplifies this process for you by doing the math for you.

This calculator uses each of the three methods listed on our one rep max main page to derive your approximate one rep maximum, and then it goes one-step further. In addition to calculating your 1RM, the One Rep Max Calculator calculates the percentage of your 1RM automatically so that you know how much weight to use for each set.

 Unit of Measure Weight pounds kilograms Reps Method 1 Method 2 Method 3 Percent of One Rep Maximum Select Method Method 1 Method 2 Method 3 % 1RM Wt. % 1RM Wt. 95% 70% 90% 65% 85% 60% 80% 55% 75% 50%

### One Rep Max Calculator Methods

The three formulas below describe how the One Rep Max Calculator arrives at your 1RM estimates.

One Rep Max Calculator Method 1:

1RM = ((Number of Reps / 30) + 1) x Weight Used

One Rep Max Calculator Method 2:

1RM = Weight Used / (1.0278 - (0.0278 x Number of Reps))

One Rep Max Calculator Method 3:

1RM = (Weight Used) x 36 / (37 - Number of Reps)

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