{
  "slug": "wilks-score",
  "title": "Wilks Score Calculator",
  "category": "Strength Training",
  "category_slug": "strength-training",
  "tier": 1,
  "summary": "Compare powerlifting totals across body weights using the 2020 Wilks coefficient.",
  "description": "This calculator computes a Wilks score using the 2020 revision of the Wilks coefficient formula, a sex-specific fifth-degree polynomial that normalizes powerlifting performance across different body weights. It requires total weight lifted (in kilograms), body weight (in kilograms), and biological sex as inputs, then outputs a dimensionless score that allows direct comparison of powerlifting totals between athletes of different sizes. The coefficient and resulting score are based on the published Wilks formula constants and represent a standardized metric widely used in competitive powerlifting.",
  "page_url": "https://fitmetriclab.com/en/tools/strength-training/wilks-score/",
  "api_url": "https://fitmetriclab.com/api/tools/wilks-score.json",
  "formula": {
    "id": "wilks_score",
    "expression": "W = T \\times \\frac{500}{a + b B + c B^{2} + d B^{3} + e B^{4} + f B^{5}}",
    "variables": [
      {
        "symbol": "T",
        "description": "Total lifted in kg"
      },
      {
        "symbol": "B",
        "description": "Body weight in kg"
      },
      {
        "symbol": "s",
        "description": "Sex (male/female)"
      }
    ]
  },
  "inputs": [
    {
      "id": "total_kg",
      "label": "Total Lifted",
      "type": "number",
      "unit": "kg",
      "default": 500,
      "min": 50,
      "max": 1500,
      "step": 1
    },
    {
      "id": "bodyweight_kg",
      "label": "Body Weight",
      "type": "number",
      "unit": "kg",
      "default": 90,
      "min": 30,
      "max": 300,
      "step": 0.1
    },
    {
      "id": "sex",
      "label": "Sex",
      "type": "select",
      "unit": null,
      "default": 1,
      "options": [
        {
          "value": 1,
          "label": "Male"
        },
        {
          "value": 0,
          "label": "Female"
        }
      ]
    }
  ],
  "worked_example": {
    "inputs": {
      "total_kg": 500,
      "bodyweight_kg": 90,
      "sex": 1
    },
    "expected_output": "319.20"
  },
  "result_summary_template": "For a lifter with a body weight of {bodyweight_kg} kg and a total lifted of {total_kg} kg, the 2020 Wilks formula estimates a relative strength score of {result}.",
  "methodology": "Applies the 2020 revision of the Wilks coefficient formula, a fifth-degree polynomial with sex-specific constants (a–f) published by Robert Wilks. The coefficient normalizes powerlifting totals across body weights, then multiplies the total lifted (kg) by the coefficient to produce the final score.",
  "sources": [
    {
      "label": "Wilks, R. Revision of Wilks Coefficient. Powerlifting Watch. 2020.",
      "url": "https://www.powerliftingwatch.com/wilks-formula"
    },
    {
      "label": "Vanderburgh PM, et al. Allometric scaling of grip strength by body mass in college-age men and women. Res Q Exerc Sport. 1995;66(1):80-84.",
      "url": "https://pubmed.ncbi.nlm.nih.gov/7777703/"
    },
    {
      "label": "International Powerlifting Federation. Technical Rules Book. IPF. 2023.",
      "url": "https://www.powerlifting.sport/rules/codes/info/technical-rules"
    }
  ],
  "faqs": [
    {
      "question": "What is a good Wilks score?",
      "answer": "Competitive raw powerlifters at national levels often score between 350–500 (male) and 300–450 (female), while world-class lifters may exceed 550 (male) or 500 (female). Beginner scores typically range from 200–300. These are descriptive observations from meet data, not performance standards."
    },
    {
      "question": "Why was the Wilks formula revised in 2020?",
      "answer": "The original 1994 Wilks coefficients were based on competition data from that era. The 2020 revision used updated meet results to recalculate the polynomial constants, reflecting improvements in training methodology, equipment, and the evolving demographics of competitive powerlifting over 25 years."
    },
    {
      "question": "Can I use my gym maxes instead of competition totals?",
      "answer": "The formula accepts any total, but the coefficients were derived from sanctioned competition lifts judged to federation standards. Gym maxes may differ from platform performance due to factors like judging depth, pause commands, and meet-day conditions, so comparisons may be less meaningful."
    },
    {
      "question": "How does the Wilks score differ from Dots or IPF Points?",
      "answer": "Wilks, Dots, and IPF Points all normalize strength across body weights but use different polynomial models and datasets. Dots (2019) and IPF Points (2019) were designed to address perceived shortcomings in Wilks, particularly at the extreme ends of the body-weight spectrum. Each federation may prefer one system."
    },
    {
      "question": "Does the 2020 Wilks formula account for age?",
      "answer": "No. The Wilks formula only adjusts for body weight and sex. Age-adjusted formulas like McCulloch, Glossbrenner, or Reshel apply additional coefficients to account for natural strength decline or development outside peak years (typically 20–40). Some federations use combined Wilks-age systems for masters categories."
    }
  ],
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    {
      "slug": "plate-calculator-kg",
      "title": "Barbell Plate Calculator (kg)",
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  ],
  "last_updated": "2026-04-22",
  "price": {
    "value": 0,
    "currency": "USD"
  },
  "runs_in_browser": true,
  "disclaimer": "Educational estimate produced from a published formula. Not medical, nutritional, or training advice. Calculations are deterministic — apply the formula to the inputs to reproduce the result."
}