Butt Size Statistics — Data, Distribution Curves, and Myth-Busting

A Note on Data Quality

Before we get into the numbers: most "butt size statistics" circulating online are garbage. They're unsourced, taken out of context, or fabricated entirely. The data in this article is drawn from peer-reviewed anthropometric studies, national health surveys, and clinical research databases.

Where data is uncertain or limited, we'll say so. That honesty is more useful than false precision.

Hip Circumference: Population Data

Hip circumference is the primary measurement used in large-scale anthropometric studies. It captures the widest point of the buttocks and is the best proxy for overall gluteal size available in population-level data.

Women (Ages 20–59)

Men (Ages 20–59)

How to read this: If your hip circumference is at the 50th percentile, half the population is larger and half is smaller. At the 25th percentile, 75% of people are larger. At the 75th, only 25% are larger. Being anywhere between the 5th and 95th percentile is entirely normal.

Waist-to-Hip Ratio: Distribution Data

Women

Men

Key insight: The WHR most commonly rated as "attractive" in research (approximately 0.67–0.72 for women) falls at or below the 5th percentile in most populations. This means the "ideal" is statistically rare — it's an extreme, not a normal target.

Gluteal Projection Data

This data comes from plastic surgery literature, as gluteal projection is not routinely measured in population surveys.

Women (Clinical Populations)

Men (Limited Data)

Caveat: This data is drawn from surgical populations, which are not representative of the general population.

Size Changes Over Time

Secular Trends in Hip Circumference (U.S. Women, NHANES)

Average hip circumference in U.S. women has increased by approximately 6 cm over three decades.

Age-Related Changes (Cross-Sectional, U.S. Women)

Hip circumference peaks in the 40–49 age group, then declines. WHR increases steadily with age as waist circumference grows relative to hips.

Myth-Busting: Claims vs. Data

"The average woman's butt is 40 inches"

Mostly true for the U.S. The NHANES median for women aged 20–59 is approximately 105 cm (41.3 inches). But this varies dramatically by country.

"Men prefer bigger butts"

Oversimplified. Research shows men prefer a specific range of WHR (roughly 0.67–0.80) more than they prefer any absolute size. Gluteal projection was a stronger attractor than raw size.

"Squats are the best exercise for building your butt"

False. EMG research consistently shows that hip thrusts produce higher gluteus maximus activation than squats.

"You can spot-reduce fat from your butt"

False. Targeted fat loss from a specific body region is not supported by any credible research.

"Your butt shape can completely change with exercise"

Partially true. You can significantly increase gluteal muscle mass, but you cannot change your skeletal structure or fat distribution pattern.

"Brazilian butt lifts are safe now"

Safer, not safe. Mortality rates have improved, but the BBL remains the cosmetic procedure with the highest mortality rate, and complication rates of 7–15% are standard.

"Cellulite means you're out of shape"

Completely false. Cellulite affects 80–90% of post-pubertal women regardless of fitness level. It is a structural feature, not an indicator of poor fitness.

Distribution Curves: How to Think About Your Data

Human body measurements follow an approximately normal (Gaussian) distribution. This means:

• 68% of people fall within one standard deviation of the mean
• 95% of people fall within two standard deviations
• 99.7% of people fall within three standard deviations

For U.S. women's hip circumference (mean 106.4 cm, SD 11.2 cm), this means:

• 68% fall between 95.2 cm and 117.6 cm
• 95% fall between 84.0 cm and 128.8 cm
• 99.7% fall between 72.8 cm and 140.0 cm

If your measurement falls anywhere in the 95% range, you are well within the normal distribution.

The Data Doesn't Lie

The overwhelming takeaway from population-level gluteal data is this: the range of normal is enormous, the "ideal" promoted by media is statistically extreme, and most people's bodies fall comfortably within the fat middle of the bell curve — even if it doesn't feel that way.

Numbers are more honest than mirrors and more reliable than social media. If you want to understand where you actually stand, start with real data.

Curious where you fall? RateMyAss.ai gives you a data-driven comparison.