One Rep Max Calculator

Your one rep max (1RM) is more than just bragging rights. Sure it let's you know how you are progressing in the gym, but it also helps you plan workout programs and change rep ranges with confidence.

In Gravitus, we compute all of your one rep maxes on the fly as you're working out. We'll let you know the instant you hit a personal record (PR) whether you were doing a max one rep effort or you were working higher rep ranges. As for your PRs, they're all neatly available on your app leaderboard so you can see instantly how your best efforts rank among your friends and the rest of the Gravitus community. We're making some of that available to everyone with this calculator. After we compute your one rep max, we'll give you the option to select an exercise and see how you rank among the Gravitus elite!

Calculate Your One Rep Max


Your one rep max is:

Compare Your Strength With Gravitus Users

Once you've computed your one rep max, compare your strength with our users. Select one of our most popular exercises below and we will let you know where you would stand on the Gravitus leaderboard for that exercise, but you'll need to get the app to solidify your position.


You're stronger than percent of Gravitus Users. Download Gravitus to maximize your training.




This calculator is only an estimation and should be treated as such. There are a lot of different equations available to compute your individual 1RM and they all give varying results. Our calculator takes the average of seven formulas: Brzycki, Epley, Lander, Lombardi, Mayhew, Oconnor, Wathan.

You can learn more about one rep max and the formulas above here.

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