Free tool

1RM Calculator

Estimate your one-rep max from any hard set — no max-out required. Enter the weight and reps, get your 1RM from five proven formulas and a %1RM table for programming.

Estimated 1RM (Epley) —

    Your %1RM loading table

    Program your working sets straight off the estimate — percentages of your 1RM and the reps typically possible at each load.

    How this calculator works

    Every estimate here comes from published equations that map a submaximal set to a predicted single: Epley (w × (1 + r/30)), Brzycki (w × 36 / (37 − r)), Lombardi (w × r0.1), O'Conner (w × (1 + 0.025r)) and Wathan. They agree closely up to about 10 reps and diverge beyond that, which is why the spread and the average are shown, not just one number.

    Why train off an estimated 1RM?

    Percentage-based programs — 5/3/1, Texas Method, most powerlifting blocks — prescribe loads as %1RM. Testing a true max every few weeks is fatiguing and risky; estimating it from your best recent set of 3–8 reps gives you the same programming anchor for free.

    Track your 1RM automatically

    FYL estimates your 1RM on every tracked exercise as you log — each set updates your strength curve, PRs and volume without opening a calculator. See everything FYL tracks, free on iOS.

    Also here: the volume calculator, the plate calculator and the warm-up calculator — all free, all on the tools hub.