Wilks Coefficient Guide
How lifters compare across bodyweight classes using a single relative-strength number.
Wilks normalises total lifted against bodyweight via a 5th-order polynomial so a 150 lb lifter and a 250 lb lifter rank on the same scale.
Absolute strength favours bigger lifters — a 250 lb lifter will almost always out-squat a 150 lb lifter. Wilks answers the different question: who is strongest for their size? It multiplies total lifted by a 5th-order polynomial fit to competitive powerlifting data. Same Wilks score means same relative strength, independent of weight class. The 2020 update refit the curve to modern data and improved extrapolation at the extremes.
Part of: Structural Output
Quick answer
Wilks normalises total lifted against bodyweight via a 5th-order polynomial so a 150 lb lifter and a 250 lb lifter rank on the same scale.
Key points
- ▸ Formula: Wilks score = total_lifted × WilksCoeff(bodyweight). Coefficient comes from a 5th-order polynomial calibrated to competitive data.
- ▸ Polynomial captures the square-cube law — cross-section grows as the square of linear dimension, mass as the cube, so relative strength decays with size.
- ▸ Gender-specific curves: male and female strength-to-mass relationships diverge at the extremes, so separate polynomials are required.
- ▸ Score bands: under 200 novice · 200-299 intermediate · 300-399 advanced · 400-499 elite · 500+ world-class.
- ▸ Bodyweight-sensitive: a 10 lb bodyweight change moves Wilks roughly 3-5 points even at the same total. Bulking without proportional strength gain drops the score.
- ▸ 2020 Wilks replaced the 1994 original with updated polynomial constants and better extrapolation beyond 140 kg and below 60 kg.
How to
- Pick gender (the coefficients are different curves).
- Enter bodyweight measured the morning of the lift, not post-meal.
- Enter either a powerlifting total or a single best lift.
- Read the coefficient and the score; check which band it lands in.
- Track the trajectory across training blocks — Wilks is the cleanest signal that bulking is producing real strength.
Examples
- 180 lb male · 1350 lb totalWilks ≈ 392 — Advanced. Add 50 lb to total and score moves ~15 points; add 10 lb bodyweight and score drops ~3 points.
- 130 lb female · 750 lb totalWilks ≈ 435 — Elite. Lighter female lifters receive a larger multiplier reflecting higher relative output.
- Two lifters · same Wilks 400Lifter A at 150 lb totals 1100. Lifter B at 250 lb totals 1500. Different absolute numbers, identical relative strength.
When to use which tool
- Strength-to-Weight Efficiency · WilksAnytime you want to rank against other lifters or track progress while bodyweight shifts.Wilks coefficient — the powerlifting gold-standard for comparing lifters across bodyweight classes.
- Max Load Capacity · Brzycki 1RMRun 1RM first to get the input totals for Wilks.Estimate one-rep maximum from a sub-max set using the Brzycki formula. Recovery / Hypertrophy / Strength zones.
- CYAN · STABLE — Wilks 200-299 — intermediate; weekly linear progression and volume accumulation still drive gains.
- GOLD · GUARDED — Wilks 300-399 — advanced; periodisation (hypertrophy → strength → peaking) required for 10-15 point gains per block.
- MAGENTA · CRITICAL — Wilks 400+ — elite; 5-10 points per year is realistic, recovery and sleep dominate training decisions.
Related
- Strength-to-Weight Efficiency · WilksWilks coefficient — the powerlifting gold-standard for comparing lifters across bodyweight classes.
- Max Load Capacity · Brzycki 1RMEstimate one-rep maximum from a sub-max set using the Brzycki formula. Recovery / Hypertrophy / Strength zones.
- Anabolic Trigger · MPS BolusPer-meal protein bolus that maximises muscle protein synthesis. 0.25-0.40 g/kg per feeding, 1.6-2.2 g/kg daily.
- Fuel Partitioning · MacrosDaily protein, fat, and carb targets anchored to bodyweight and training goal. Protein-first, fat floor second, carbs fill.
- The Wilks CoefficientHow powerlifters compare a 150 lb lifter to a 250 lb lifter fairly.
- Interpreting Your Wilks ScoreWhere you sit in the novice-intermediate-advanced-elite spectrum.
- Wilks Formula PitfallsThe conditions where Wilks over- or under-states relative strength.
Frequently asked questions
› Is Wilks better than DOTS or IPF Points? Comparison
DOTS and IPF Points are newer alternatives with slightly different curves at the extremes. Rankings correlate tightly in the dense middle of weight classes. Pick whichever your federation uses and stay consistent.
› Does Wilks work for single lifts?
Yes — enter the single best lift where the calculator asks for total. The absolute band numbers shift (a 400 squat-only Wilks is not the same as a 400 total Wilks) but relative normalisation still holds.
› Why does my Wilks drop when I bulk? Troubleshooting
Bodyweight sits in the polynomial denominator effectively. Unless your total climbs proportionally, adding 10 lb of bodyweight costs 3-5 points. Wilks is the cleanest test of whether a bulk actually bought strength.
› How should I use this guide with a Kefiw tool? How-to
Use the guide as the plan and the linked Kefiw tool as the check. Read the steps first, try the move manually, then use the tool to compare outputs, catch edge cases, and decide whether the result actually fits your task.
› What mistake do tool guides help avoid? Troubleshooting
Tool guides help avoid using a utility mechanically without understanding what you are trying to accomplish. Most word, writing, and text utilities are fast, but speed can hide context mistakes. Know whether you are solving a puzzle, cleaning copy, drafting a line, or checking a rule.