1 Rep Max Calculator is a free Android app that allows users to calculate their one repetition maximum for almost any weightlifting exercise. The app uses the Epley Formula to accurately calculate the one rep max for bench press, deadlift, squat, and other lifts. Users can create custom lifts and track their one rep max for any exercise. The app also includes a weight percentage quick reference guide and visual progress graphs.

Calculating your one rep max before attempting it can help prevent injury and the app provides you with a strength estimate. However, the accuracy of the one rep max calculations can vary depending on the weight training experience and muscular composition of the athlete using the calculator. The app is designed for seasoned strength trainers, and those with lesser experience may find their actual one rep maximum is much lower due to their nervous system not being able to handle the stress of a high weight.

It is important to lift responsibly and heavy weightlifting should always be performed with a spotter for safety.