Wilks Score Calculator

Wilks Score is Total Lifted (converted to kg) multiplied by a Wilks Coefficient that depends only on Body Weight and Gender. The coefficient comes from 500 divided by a fifth-degree polynomial in body weight, using one set of six coefficients (a through f) for men and a completely different set for women — the two sexes are not scaled versions of each other, they use separately fit curves. Because the coefficient is a smooth function of body weight, small body-weight changes barely move the final score; Total Lifted enters as a flat multiplier, so the same percentage change in your total moves Wilks Score by that same percentage every time. The single biggest lever on the score, though, is Gender itself: because the male and female curves are separately fit polynomials rather than scaled versions of one another, which table you're scored against moves Wilks Score more than an ordinary change in Total Lifted or Body Weight does.

The whole point of the coefficient curve is to flatten out the natural advantage lighter lifters have on a percentage-of-bodyweight basis, so it is designed to respond weakly to body weight — a lifter who gains 10 lb without adding to their total will see Wilks Score move only slightly. This is the classic 1994 Wilks formula (not the 2020 Wilks-2 revision some federations now use), and it does not account for age, equipment, or drug-tested vs. unequipped divisions. Vanderburgh and Batterham's 1999 validation study in Medicine & Science in Sports & Exercise tested the classic Wilks formula against a large powerlifting dataset and found it unbiased across bodyweight classes for bench press and total, though it did identify a linear bias favoring lighter lifters specifically on the deadlift.