Your one rep max is the most weight you can lift for a single repetition, and estimating it from a lighter set you actually completed is safer than testing a true max. This calculator applies four respected formulas at once so you can compare them. Epley multiplies the weight by one plus reps divided by thirty, Brzycki divides by a reps based factor, and the Lombardi and Lander equations use their own curves. Enter the weight lifted and the number of clean repetitions, and each estimate appears together along with an average. Accuracy is best in the one to ten rep range, since very high rep sets stray from these models. Everything is computed locally in your browser and nothing is uploaded. Use the result to plan training percentages, and always lift within your ability with proper form and a spotter.
It estimates your one rep max with the Epley, Brzycki, Lombardi and Lander formulas so you can compare four results.
Estimates are most reliable in the low rep range, so a set of around 2 to 10 reps gives a closer figure than very high rep sets.
Each formula models the rep to weight relationship slightly differently, so they diverge more as the rep count rises.
Your one rep max is the most weight you can lift for a single repetition, and estimating it from a lighter set you actually completed is safer than testing a true max. This calculator applies four respected formulas at once so you can compare them.
Yes. One Rep Max Multi Formula Calculator is completely free, with no sign-up and no usage limits.
Yes. One Rep Max Multi Formula Calculator runs in any modern web browser. There is nothing to download or install.
Yes. One Rep Max Multi Formula Calculator runs entirely on your device in your browser, so nothing you enter is uploaded to a server.