Wilks calculator

How your Wilks score is calculated

A Wilks score turns a total, or a single lift, into a number you can compare across body weights and between men and women, the same job DOTS and the IPF's GL points do with their own formulas. Wilks does it with a six-term, fifth-degree polynomial of body weight, one degree higher than DOTS's five-term polynomial, fitted separately for men and women by Robert Wilks of Powerlifting Australia in the 1990s.

The formula, spelled out

Wilks coefficient = 500 ÷ (a + b·x + c·x² + d·x³ + e·x⁴ + f·x⁵), where x is body weight in kilograms and a to f are six fixed coefficients, different for men and women. Score = total (or single lift) × coefficient.

The coefficients this calculator uses

Men: a = minus 216.0475144, b = 16.2606339, c = minus 0.002388645, d = minus 0.00113732, e = 0.00000701863, f = minus 0.00000001291. Women: a = 594.31747775582, b = minus 27.23842536447, c = 0.82112226871, d = minus 0.00930733913, e = 0.00004731582, f = minus 0.00000009054. These are the coefficients in the OpenPowerlifting project's scoring code, and they reproduce Robert Wilks' own published coefficient table to four decimals (69.3 kg gives 0.7552 for men in both). His table runs from 40 to 205.9 kg for men and 40 to 150.9 kg for women; past about 200 kg the men's curve flattens and starts to turn back up, so this calculator holds the coefficient at 200 kg for men and 150 kg for women rather than extrapolating.

A worked example, checked against a real result

Take an 83 kg man with a 600 kg total, the same lifter used as the worked example on the DOTS calculator page. His polynomial value works out to roughly 749.1, so his coefficient is 500 divided by 749.1, about 0.6675, and his total times that coefficient gives roughly 400.5 Wilks. As a check against a real competition rather than a made-up example, Nurlan Yeshmakhanov weighed in at 117.6 kg and totalled 1,045 kg at the 2017 World Games, a result listed at 603.70 Wilks. Running the same body weight and total through the formula above gives 603.71. The published figure uses the coefficient rounded to four decimals, 0.5777 as in Wilks' own table, and 1,045 times 0.5777 is 603.70 exactly.

Wilks2 (2020): what changed

Robert Wilks released a revised formula through Powerlifting Australia in early 2020, commonly called Wilks2 or the Wilks 2020 formula, with new coefficients for men and women based on new data. The stated aim was to rebalance the coefficients so that men's and women's performances line up better and the extreme body weight classes sit in better balance with the middle ones.

The formula changed shape, not just the numbers

Wilks2 also swapped the numerator from 500 to 600: coefficient = 600 ÷ (a + b·x + c·x² + d·x³ + e·x⁴ + f·x⁵), with its own six coefficients for men and women. Men: a = 47.4617885411949, b = 8.47206137941125, c = 0.073694103462609, d = minus 0.00139583381094385, e = 0.00000707665973070743, f = minus 0.0000000120804336482315. Women: a = minus 125.425539779509, b = 13.7121941940668, c = minus 0.0330725063103405, d = minus 0.0010504000506583, e = 0.00000938773881462799, f = minus 0.000000023334613884954. These are the constants in the OpenPowerlifting project's Wilks2020 code, which notes that Wilks first published only coefficient tables and that this formula definition, dated 9 March 2020, was sent by Wilks to the USPA.

Wilks2 numbers are not Wilks numbers

Because the numerator moved from 500 to 600 on top of the rebalanced curve, a Wilks2 score runs noticeably higher than an original Wilks score for the exact same lift. The 83 kg, 600 kg lifter above scores roughly 400.5 under the original formula and roughly 481.0 under Wilks2, a difference of scale, not of who lifted better. Never compare a Wilks2 number against an original Wilks number, or against a Wilks-based "what is a good score" table, without converting one of them first.

Why Wilks was replaced

Wilks was the standard cross-body-weight formula in powerlifting for roughly two decades, but by the late 2010s two separate federations had moved to their own replacements.

A documented bias

A 1999 validation study, using world record holders and the top finishers at the 1996 and 1997 IPF World Championships, found Wilks held up well for bench press and total, but carried a bias against heavier lifters in the deadlift and towards intermediate weight classes in the women's squat, the same finding referenced on this site's DOTS calculator page. The same paper pointed out that the formula was not based on published data.

The IPF's path

The International Powerlifting Federation switched from Wilks to its own IPF Formula in 2018, then replaced that formula with IPF GL points, effective from 1 May 2020, after its 2019 evaluation found the 2018 formula still was not balanced and fair to all lifters. GL points is an exponential model, not a polynomial like Wilks, DOTS or Wilks2.

USA Powerlifting's path

USA Powerlifting, the IPF's American affiliate, used the IPF's own points formula while it held that affiliation, an arrangement that ended when the IPF expelled USA Powerlifting in November 2021. Today USA Powerlifting, like the USPA and most federations outside the IPF, scores Best Lifter with DOTS rather than Wilks.

Wilks compared with DOTS and IPF GL points

All three formulas solve the same problem, ranking lifters of different body weights on one scale, but they are not interchangeable numbers.

Wilks vs DOTS

DOTS is a fourth-degree, five-term polynomial published by Tim Konertz in 2019; Wilks is a fifth-degree, six-term polynomial from the 1990s. For a raw total, the two land in a similar numeric range, the 83 kg, 600 kg lifter above scores about 400.5 Wilks and about 405 DOTS, but that closeness is not guaranteed at every body weight, since the two curves were fitted to different data at different times.

Wilks vs IPF GL points

GL points runs on a roughly 0 to 100 scale using an exponential model, so a GL score and a Wilks score are never close numbers even for the same lift; only their ranking of lifters is comparable, not the figures themselves.

Which one to use

For an official Best Lifter award, use whichever formula that specific federation runs, since that is the number that decides the placing. Outside a specific federation's meet, Wilks remains widely recognised and is still what many older meet records, spreadsheets and lifting apps report, which is the main reason to calculate it today.

Wilks score at a glance

These bands are informal community benchmarks for a raw, tested lifter's total under the original Wilks formula, not an official classification from any federation. They line up closely with the bands commonly used for DOTS, since the two formulas sit on a similar scale for a total. They do not apply to a Wilks2 score, which runs higher for the same lift.

How to use your Wilks score

A single Wilks number is a snapshot. It becomes useful once you track it over time or use it to judge a change in body weight honestly.

Track it over time

Recalculate whenever you hit a new total or your body weight shifts. A rising Wilks score confirms you are getting stronger relative to your size, not just heavier and lifting proportionally more.

Judge a cut or a bulk honestly

Take the 83 kg, 600 kg lifter from above, sitting at roughly 400.5 Wilks. Cut to 78 kg while the total slips to 580 kg, giving up 20 kg on the bar, and the score comes out to about 402.5, a small increase despite lifting less weight, because the coefficient at 78 kg grew faster than the total shrank. Bulk from 83 kg to 93 kg instead and the total climbs to 630 kg, a real 30 kg gain on the bar, and the score drops to about 395.8, below where it started, because a heavier body weight needed more than that to keep pace. Neither outcome is visible from the bar total alone.

Using Wilks for a single lift instead of a total

The arithmetic does not care what number goes in, so you can enter a best squat, bench or deadlift instead of a full total. This is not the formula's official use, Wilks was built and validated against full powerlifting totals, so a single-lift Wilks score has no competition standing and should not be read against the total-based bands above.

It is still a consistent way to track your own squat, bench or deadlift against your own body weight over time. Take a 90 kg man benching 140 kg, scoring roughly 89.4 Wilks. Six months later, at the same body weight, his bench is up to 145 kg, for roughly 92.6 Wilks, a clean read on how much the bench specifically improved with body weight held constant.

Common mistakes

Comparing a Wilks2 score against an original Wilks score. They run on different scales, 500 versus 600 in the numerator, on top of different coefficients. A 450 Wilks2 is not the same achievement as a 450 Wilks.

Comparing a single-lift score against the total bands. A 400 Wilks bench is not the same achievement as a 400 Wilks total.

Mixing formulas mid-comparison. A Wilks score, a DOTS score and an IPF GL score from the same lift are three different numbers, even though they measure the same idea.

Reading a score outside the validated body weight range as exact. Below 40 kg, or above roughly 200 kg for men and 150 kg for women, you are past the range Wilks' own coefficient table covers.

Forgetting the total needs all three lifts. Squat plus bench plus deadlift, each your best successful attempt, not your best of each across different sessions.

How coaches use a Wilks calculator

For a coach with clients across a wide range of body weights, Wilks is a fast way to put everyone on one scale, whether that is comparing two clients directly or judging whether a client's own number is trending up.

A practical routine is the same one that works for DOTS: log body weight and working totals at the end of each training block, recalculate, and look at the trend rather than the raw total in isolation, especially around a cut or a bulk where the bar total alone can be misleading either way.

Scraler keeps that history next to everything else instead of a spreadsheet. Log lift PRs and body weight through workout tracking, and review a client's numbers with them as part of a regular check-in rather than chasing screenshots from a training log. To score a single lift rather than a total, or to estimate a max from a set of reps, use the one rep max calculator.