Wilks Formula Calculator
Calculate your powerlifting strength relative to your body weight using the Wilks coefficient.
Wilks Calculator
Wilks = ( Total Weight Lifted (kg) ^ (Ratio to Bodyweight) ) / ( (Coefficient A)
*Note: Coefficients A, B, and C are specific to gender and are determined by the International Powerlifting Federation (IPF).
Select your gender for accurate coefficient calculation.
Enter your bodyweight in kilograms.
Enter the sum of your best squat, bench press, and deadlift in kilograms.
Results
Key Assumptions
What is the Wilks Formula?
The Wilks formula is a standardized method used in the sport of powerlifting to equalize the strength of competitors across different bodyweight classes. Developed by powerlifting coach and statistician Ken Wilks, this formula allows for a more objective comparison of strength by providing a “Wilks coefficient” or “Wilks score.” Essentially, it calculates a lifter’s strength relative to their body mass. A higher Wilks score indicates greater relative strength.
Who Should Use It?
Anyone involved in competitive powerlifting, or even serious recreational lifters aiming to track their progress and compare themselves to others within their weight class or across different weight classes, will find the Wilks formula invaluable. It’s particularly useful for comparing lifters in unsanctioned meets or when comparing results from different federations that might use varying bodyweight class structures.
Common Misconceptions
A common misconception is that the Wilks formula only benefits lighter lifters. In reality, it benefits all lifters by providing a common metric. Another misconception is that it perfectly accounts for every physiological difference; while it’s an excellent tool, individual leverages, training history, and genetics also play significant roles in strength performance, which the formula doesn’t directly measure. It’s a statistical tool, not a perfect predictor of every individual’s potential.
Wilks Formula and Mathematical Explanation
The Wilks formula is designed to normalize the total weight lifted by a powerlifter across different body weights. The core idea is that heavier individuals can naturally lift more absolute weight due to biomechanical advantages, but relative strength (strength per unit of body mass) might be higher in lighter individuals. The formula aims to capture this nuance.
The original Wilks formula, and the one predominantly used today, is:
Wilks Score = Total Weight Lifted (kg) / ( (A – B*Bodyweight + C*Bodyweight^2 – D*Bodyweight^3 + E*Bodyweight^4 – F*Bodyweight^5) )
Where A, B, C, D, E, and F are coefficients that vary based on gender. These coefficients were derived statistically to best fit the observed strength-to-bodyweight ratios across a wide range of lifters.
For males:
A = 107.5
B = 0.00007294
C = 0.00000007875
D = 0.000000000025
E = 0.0000000000000039
F = 0.00000000000000000035
For females:
A = 85.6
B = 0.00008712
C = 0.0000001028
D = 0.0000000000309
E = 0.0000000000000050
F = 0.00000000000000000060
The calculation involves raising the bodyweight to different powers and then using these results in a polynomial function to determine the denominator. This denominator effectively acts as a divisor that adjusts the raw total lifted for bodyweight.
Variable Explanations
| Variable | Meaning | Unit | Typical Range |
|---|---|---|---|
| Total Weight Lifted | The sum of the heaviest successful attempt in the squat, bench press, and deadlift. | Kilograms (kg) | Varies widely (e.g., 100 kg to over 1000 kg) |
| Bodyweight | The lifter’s body mass at the time of the competition. | Kilograms (kg) | Varies widely (e.g., 40 kg to over 150 kg) |
| A, B, C, D, E, F | Gender-specific coefficients used in the polynomial calculation to adjust for bodyweight. | Unitless (Coefficients) | Fixed values based on gender |
| Wilks Score | The calculated relative strength score. | Unitless (Coefficient) | Varies widely (e.g., 200 to over 600) |
Practical Examples
Let’s illustrate the Wilks formula with two distinct examples: one male and one female lifter, demonstrating how the formula normalizes strength across different bodyweights.
Example 1: Male Lifter
Lifter Profile: John, a male powerlifter.
- Bodyweight: 95.0 kg
- Best Squat: 200 kg
- Best Bench Press: 150 kg
- Best Deadlift: 250 kg
- Total Weight Lifted: 200 + 150 + 250 = 600 kg
Using the male coefficients:
A = 107.5, B = 0.00007294, C = 0.00000007875, D = 0.000000000025, E = 0.0000000000000039, F = 0.00000000000000000035
Calculation Steps:
- Calculate the denominator polynomial:
D = 107.5 – (0.00007294 * 95.0) + (0.00000007875 * 95.0^2) – (0.000000000025 * 95.0^3) + (0.0000000000000039 * 95.0^4) – (0.00000000000000000035 * 95.0^5)
D ≈ 107.5 – 0.0069293 + 0.71028125 – 0.021115625 + 0.00645639375 – 0.00001838353125
D ≈ 111.886 - Calculate Wilks Score:
Wilks = 600 kg / 111.886 ≈ 5.362
Interpretation: John’s Wilks score is approximately 5.36. This score allows him to be compared against lifters in other weight classes. For example, a 75 kg lifter lifting 500 kg would have a significantly different Wilks score.
Example 2: Female Lifter
Lifter Profile: Sarah, a female powerlifter.
- Bodyweight: 70.0 kg
- Best Squat: 160 kg
- Best Bench Press: 90 kg
- Best Deadlift: 190 kg
- Total Weight Lifted: 160 + 90 + 190 = 440 kg
Using the female coefficients:
A = 85.6, B = 0.00008712, C = 0.0000001028, D = 0.0000000000309, E = 0.0000000000000050, F = 0.00000000000000000060
Calculation Steps:
- Calculate the denominator polynomial:
D = 85.6 – (0.00008712 * 70.0) + (0.0000001028 * 70.0^2) – (0.0000000000309 * 70.0^3) + (0.0000000000000050 * 70.0^4) – (0.00000000000000000060 * 70.0^5)
D ≈ 85.6 – 0.0060984 + 0.50372 – 0.0104949 + 0.012005 – 0.0000178506
D ≈ 91.195 - Calculate Wilks Score:
Wilks = 440 kg / 91.195 ≈ 4.825
Interpretation: Sarah’s Wilks score is approximately 4.825. Comparing this to John’s score of 5.36, even though John lifted more absolute weight (600 kg vs 440 kg), Sarah’s relative strength is quite competitive when adjusted for bodyweight. This highlights the fairness of the Wilks system.
How to Use This Wilks Formula Calculator
Our Wilks Formula Calculator is designed for simplicity and accuracy, providing you with your relative strength score in seconds. Follow these easy steps:
- Select Gender: Choose your gender (Male or Female) from the dropdown menu. This is crucial as the Wilks coefficients differ significantly between genders.
- Enter Bodyweight: Input your precise bodyweight in kilograms (kg) into the ‘Bodyweight (kg)’ field. Ensure accuracy for the best results.
- Enter Total Lifted: Input the sum of your best Squat, Bench Press, and Deadlift attempts in kilograms (kg) into the ‘Total Weight Lifted (kg)’ field. This is your competition total.
- Calculate: Click the ‘Calculate Wilks’ button. The calculator will instantly process your inputs.
How to Read Results:
- Primary Result (Wilks Score): The large, highlighted number is your Wilks coefficient. A higher score indicates greater relative strength. Compare this score to leaderboards or other lifters to gauge your standing.
- Intermediate Values: These provide context, showing the specific ‘Coefficient A’ used for your gender, the ratio of your total lifts to your bodyweight, and confirmation of the formula variant.
- Key Assumptions: These boxes confirm the inputs you provided (Gender, Bodyweight, Total Lifts), ensuring the calculation is based on your correct data.
Decision-Making Guidance:
Use your Wilks score to set realistic performance goals. For instance, if you aim to qualify for a specific competition, research the typical Wilks scores of successful competitors in your target divisions. If your score is lower than desired, focus on improving your total lift weight, especially in your weaker lifts, while managing your bodyweight effectively. A strategic approach to training and nutrition can significantly impact your Wilks score over time. Consider using this calculator periodically to track improvements in your relative strength.
Key Factors That Affect Wilks Results
While the Wilks formula provides a standardized way to measure relative strength, several underlying factors influence both your performance and, consequently, your Wilks score. Understanding these is key to effective training and strategic improvement.
- Bodyweight Management: This is the most direct factor. Gaining or losing weight (muscle or fat) will change your bodyweight input. A lower bodyweight, with the same total lift, will increase your Wilks score. However, significant weight changes can also impact strength potential. Strategic weight class management is a common tactic in competitive powerlifting.
- Strength Progression in Lifts: The Wilks formula is directly tied to your total lifted weight. Improvements in your squat, bench press, and deadlift will directly increase your Wilks score. Consistent, progressive overload in training is paramount.
- Training Specialization: Some lifters excel at one specific lift (e.g., deadlift) but are weaker in others (e.g., bench press). The Wilks formula benefits from a balanced strength profile across all three lifts. Focusing on weaknesses can yield significant gains in the overall Wilks score.
- Technique and Efficiency: Perfecting lifting technique can often lead to lifting more weight with the same effort or even less. Proper form, understanding leverages, and efficient movement patterns can significantly boost your total lifted, directly improving your Wilks score without necessarily increasing muscle mass.
- Genetics and Leverage: While the Wilks formula tries to account for body size, individual genetic predispositions (muscle insertions, limb lengths, tendon insertions) affect how efficiently someone can produce force in specific lifts. These inherent physical characteristics are not directly factored into the Wilks calculation but heavily influence the raw numbers.
- Age and Recovery: As lifters age, recovery capacity might change, impacting training intensity and volume. While the Wilks formula itself doesn’t have an age component, the ability to train effectively and recover sufficiently to maximize lifted weight is age-dependent. Younger lifters might recover faster, allowing for more aggressive training cycles that could lead to higher Wilks scores.
- Nutrition and Supplementation: Optimal nutrition supports muscle growth, repair, and energy levels, all critical for maximizing strength performance. Proper fueling and recovery through diet can directly translate to higher lifted weights and, therefore, better Wilks scores.
- Competition Day Factors: Factors like peaking for a competition, managing nerves, weight cuts, and even equipment (if applicable in certain federations) can influence the total weight lifted on a given day, thus affecting the Wilks score achieved in that competition.
Frequently Asked Questions (FAQ)
Related Tools and Internal Resources
To further enhance your powerlifting journey, explore these related tools and resources:
Wilks Score vs. Bodyweight
Female Lifter Data