Sinclair Weightlifting Coefficient Calculator
The Sinclair coefficient lets you compare Olympic weightlifting performances across bodyweights on a single scale. It scales a lifter's total to what they might have lifted at the reference bodyweight of the heaviest competitor. Enter your bodyweight, your competition total, and the A and b parameters for the relevant Olympic cycle to get your Sinclair coefficient and Sinclair total. Because the International Weightlifting Federation revises the parameters each cycle, they are provided as editable inputs so the result always reflects the values you are scoring against.
Sinclair coefficient formula
If X ≤ b: coefficient = 10^(A * (log10(X / b))^2)
If X > b: coefficient = 1
Sinclair total = total lifted * coefficient
where X = bodyweight, A and b = IWF cycle parameters
The coefficient is 1.0 at the reference bodyweight b and rises above 1.0 for lighter lifters, scaling their total upward for fair comparison. Lifters heavier than b receive a coefficient of 1.0.
Worked example
An 85 kg lifter totals 320 kg. Using A = 0.722762521 and b = 193.609: log10(85 / 193.609) = log10(0.43903) = -0.35751. Squared = 0.12781. Times A = 0.09238. 10^0.09238 = 1.2370 coefficient. Sinclair total = 320 * 1.2370 = 395.85.
Sinclair coefficient: frequently asked questions
What is the Sinclair coefficient?
The Sinclair coefficient is a multiplier used in Olympic weightlifting to compare lifters of different bodyweights. It estimates what a lifter would have totaled if they had the bodyweight of the heaviest competitor in their gender category, allowing a fair comparison across weight classes.
What is the Sinclair formula?
If your bodyweight X is less than or equal to the world record holder bodyweight b, the coefficient is 10^(A*(log10(X/b))^2). If X is greater than b, the coefficient is 1. Your Sinclair total is then your total lifted weight multiplied by this coefficient. A and b are parameters published by the International Weightlifting Federation for each Olympic cycle.
What are the current A and b parameters?
The A coefficient and b reference bodyweight are set by the International Weightlifting Federation and revised each Olympic cycle. Because they change, this calculator provides them as editable inputs with published defaults so you can enter the values for the cycle you are scoring. Always confirm the current parameters on the IWF website before using results competitively.
Does a higher Sinclair total mean a better lift?
Yes. The Sinclair total normalises for bodyweight, so a higher Sinclair total indicates a relatively stronger performance regardless of weight class. It is the basis for many best-lifter awards at weightlifting competitions.
Sources
- International Weightlifting Federation: official site and Sinclair coefficient parameters.
Reviewed by the CalculatorHub team, edited by James Graham, 19 June 2026. See our methodology.