1RM Calculator – One Repetition Maximum

What is 1RM (One Repetition Maximum)?

1RM, or one repetition maximum, is the maximum amount of weight you can lift for a single rep of a given exercise. It is a popular metric in strength training for assessing maximum strength and tracking progress.

Use the calculator below to estimate your 1RM based on the number of repetitions and weight. This tool uses the Epley formula – one of the most widely used methods.