Worked example: a 500 kg total at 90 kg bodyweight
| Formula | Coefficient | Score | Status |
|---|---|---|---|
| DOTS (2019) | 0.6466 | 323.30 | Current |
| Wilks (1994) | 0.6384 | 319.20 | Retired by the IPF in 2020 |
Squat 180 kg, bench 120 kg, deadlift 200 kg. The two formulas differ by 4.1 points on the same lifter, which is about 1.3%. That gap is small in the middle of the bodyweight range and grows at both ends — which is the whole reason DOTS was fitted.
What these scores are for
A total on its own cannot be compared across bodyweight classes. A 500 kg total is an entirely different achievement at 60 kg than at 120 kg, and a competition that awards a single “best lifter” prize needs one column to sort on. Wilks and DOTS both exist to produce that column: a coefficient derived from bodyweight, multiplied by the total.
They are ranking devices, not judgements. Neither says anything about how strong you should be, what your training should look like, or whether the number is good. A DOTS score is only meaningful against other DOTS scores.
Why there are two of them, and which to use
Wilks was published by Robert Wilks in 1994 and became the IPF standard. It is a fifth-order polynomial in bodyweight, with separate coefficients for men and women. Over twenty-five years the lifting population moved — particularly at the heavier end and in women's classes — and the formula drifted out of calibration against it.
The IPF replaced Wilks with its own IPF GL points in 2020. DOTS, a four-term refit published independently in 2019, was adopted by a large part of the rest of the sport and by most gym leaderboards and tracking apps.
Use DOTS for anything current. Keep Wilks when you are comparing against a record set before 2020, because that record is a Wilks number and converting it silently would compare two different scales.
Methodology
Both formulas take the same shape: a coefficient of 500 ÷ P(bodyweight), where P is a polynomial with published constants, and the score is that coefficient multiplied by the total lifted in kilograms. Wilks uses six terms (constant through bodyweight to the fifth power); DOTS uses five. Each has a separate constant set for men and for women. Imperial input is converted to kilograms first — the polynomials are defined on kilograms and there is no pounds variant.
The coefficients are transcribed from the published formulas, not re-derived. The test suite for this site carries the same constants written out independently, so a transcription error shows up as a failing test rather than as a plausible-looking wrong score.
Limitations
Both polynomials are only valid over the bodyweight range they were fitted on. We clamp bodyweight to 40–200 kg for men and 40–150 kg for women. Outside that range a fifth-order polynomial does not gently lose accuracy — it turns over and starts returning numbers that are simply wrong, including negative ones. If your bodyweight is clamped, the page says so above the result.
Neither formula distinguishes raw from equipped lifting, tested from untested federations, or a full-depth competition squat from a gym squat. Two identical scores can represent very different lifts, and the number is only comparable inside whichever of those worlds you are in.
Both were fitted on competitive powerlifters, so they describe that population best. A recreational lifter's score is still arithmetic, and still correct arithmetic, but the population it is being compared against is not the population they are in.
The bands we print beside the score are a reading convention, not percentiles from a random sample. There is no representative dataset of everybody's DOTS score, and anyone presenting one has sampled people who log lifts, which is a different thing entirely.
This is a strength-sport score, not medical advice and not a training prescription. Attempting a maximal single is the part of this that carries risk; do it warmed up, in a rack or with a spotter, and not because a web page gave you a number to chase.