One Rep Max Calculator is a free iPhone app developed by Charles Vanderhoff. It falls under the Lifestyle category and specifically the Health & Fitness subcategory. This app allows users to calculate their one rep max for various weightlifting exercises.

With One Rep Max Calculator, you simply input the weight you lifted and the number of repetitions, and the app will calculate your one rep max. This is especially useful for those who want to track their progress and set goals for their lifts. The app also provides graphs to visualize your progress over time.

One Rep Max Calculator is not limited to standard exercises. Users can create custom lifts and track their one rep max for any exercise they choose. This makes it a versatile tool for powerlifters, Olympic weightlifters, and CrossFitters.

It's important to note that the accuracy of the one rep max calculations can vary depending on the user's weight training experience and muscular composition. The app is designed for seasoned strength trainers, and those with less experience may find their actual one rep maximum to be lower.

Overall, One Rep Max Calculator is a helpful tool for weightlifters looking to calculate their one rep max and track their progress. However, it's important to lift responsibly and have a spotter for safety during heavy weightlifting sessions.