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Allometric Scaling Calculator

See how your lifts scale with bodyweight using power-law curves from 2.5M+ competition results.

Your Stats

Power-Law Scaling Curve

The curve shows how typical competition totals scale with bodyweight (Total = a x BW^b). Your dot shows where you fall relative to the population.

Allometric Standards by Weight Class

Weight Class P50 Total P75 Total P90 Total Allometric Factor

Weight Class Shift Analysis

What moving up or down a weight class means for your projected total based on population data.

Related Calculators

Strength Benchmarks See your exact percentile vs 2.5M+ competition results Weight Class Optimizer Should you move up or down a weight class? Lift Ratio Analyzer Check your S/B/D split vs your weight class cohort

What Is Allometric Scaling?

Allometric scaling describes how biological traits change with body size. In powerlifting, strength does not scale linearly with bodyweight - a lifter who weighs twice as much is not twice as strong. Instead, strength scales with bodyweight raised to an exponent (typically 0.63 to 0.67), forming a power-law curve.

The formula is: Lift = a x Bodyweight^b, where b is the allometric exponent. For powerlifting totals, b is approximately 0.65, meaning each 1% increase in bodyweight predicts about a 0.65% increase in total. This is why scoring systems like DOTS and IPF GL exist - to adjust for this non-linear relationship.

This calculator plots your lifts against the power-law curve derived from 2.5M+ competition results, showing whether your strength is above or below what the model predicts for your bodyweight.

Frequently Asked Questions

Muscle cross-sectional area (which determines force production) scales with the square of a linear dimension, while body mass scales with the cube. Since bigger lifters have proportionally more mass per unit of muscle area, strength gains with bodyweight but at a diminishing rate. This is captured by the allometric exponent - typically around 0.65 for powerlifting totals.
The allometric ratio is your actual lift divided by the predicted lift for your bodyweight. A ratio above 1.0 means you are stronger than the model predicts (above the curve). Below 1.0 means you are below the curve. This is a bodyweight-normalized measure of relative strength similar to Wilks or DOTS, expressed as a simple ratio.
Moving up a weight class increases your predicted total (the denominator), so your ratio may stay the same or drop unless you actually get stronger. The weight class shift analysis shows the tradeoff: how much projected total you gain from the additional bodyweight allowance versus how much you need to lift to maintain your allometric ratio.
Wilks and DOTS use polynomial formulas to normalize totals across bodyweights, giving a single number score. Allometric scaling uses a power-law model to show the expected curve across the full bodyweight range, making it easy to see where you fall relative to the population at any bodyweight, not just your own.
Yes. Female lifters tend to have slightly lower allometric exponents, particularly for upper body lifts like bench press. This reflects differences in how muscle mass distributes between upper and lower body across the weight spectrum. This calculator uses sex-specific coefficients derived from competition data.