Average Thigh Size for Women by Age (and What It Means for Your Thigh Band Size)

Search for "average thigh size for women" and almost every answer repeats one number: 20.8 inches. That figure is real, but it comes from a tape measure placed at the middle of the thigh, halfway between the hip crease and the knee. Thigh bands, slip shorts, and most anti-chafe products are sized at a different spot, the fullest part of the upper thigh, where the inner thighs actually touch. Mixing the two up is one of the most common reasons women order the wrong size.

This page puts the official U.S. numbers in one place, by age, explains why your upper-thigh measurement will almost always be bigger than the "average," and shows how to turn your own measurement into the right thigh band size. Everything here comes from public U.S. government data, with the sources and limitations listed at the end.

Average Thigh Size for Women by Age

The table shows the average (mean) and middle (median) mid-thigh circumference for U.S. women, from the CDC's National Health and Nutrition Examination Survey (NHANES). Half of women in each age group measure below the median and half above it.

What the numbers show

• Thigh size rises through the 20s and 30s and peaks in the 40s, at 54.4 cm (21.4 in).
• For women aged 40 to 69, the core Trendyvice audience, averages stay within about 2 cm of each other, from 52.2 to 54.4 cm.
• Averages fall more clearly in the 70s and 80s, to 49.6 cm and 47.5 cm.
• In every age group, the median is lower than the mean, which means a smaller number of women with larger thighs pull the average up.

Mid-Thigh vs Upper Thigh: Why Your Band Size Is Bigger

Where the tape sits changes the number more than almost anything else. U.S. survey data measured three different spots on the thigh:

The two surveys measured different groups of women, so the gap is a guide, not an exact conversion. But the direction is clear: if you measure the middle of your thigh by mistake, you will choose a band that is too small, and a band that is too small digs in and can leave marks. For more on fit problems, see What Size Thigh Bands Should I Get?

What This Means for Your Thigh Band Size

Here is the Trendyvice lace thigh band size chart. Every range is an upper-thigh measurement, taken where the band will sit.

Put the survey numbers next to the chart and two things stand out. The average upper-thigh measurement of 61.6 cm lands right in the middle of size D (58–65 cm). The mid-thigh "average" of 52.9 cm would point you to size C, one size smaller, which is exactly the mistake to avoid. Your own measurement is what counts, so use these averages as a sense check, not as your size.

How to measure your upper thigh for thigh bands

• Stand with your feet about hip-width apart and your weight on both legs.
• Wrap a soft tape around the fullest part of your upper thigh, just below the buttock crease, where the band will sit.
• Keep the tape level and snug, without pulling it tight.
• Measure both thighs. They are often slightly different, so use the larger number.
• If your measurement fits two sizes, choose the one where you sit nearer the middle of the range.

The full measuring guide, with photos and answers to common fit questions, is in the Thigh Band Fit & Buying Guide.

What Your Thigh Size Does Not Mean

An average describes a population, not a target. A tape measure cannot tell muscle from fat, and a number above or below the average is not good or bad. Thighs that touch are normal at every size: hip width, bone structure, and muscle all decide whether the inner thighs meet when you walk. That is why chafing happens to slim and athletic women too, as we explain in Does Thigh Chafing Mean You're Fat? An Honest Answer.

The Right Size, Without the Guesswork

Once you know your upper-thigh measurement, choosing a band is simple. The Lace Anti-Chafe Thigh Bands 4-Pack covers sizes S to F, from 36 to 78 cm (14.2 to 30.7 in), with four pairs in black, white, beige, and red, so there is a pair for every dress and a spare for long days.

Lace Anti-Chafe Thigh Bands 4-Pack

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Wrong-Size Guarantee: if the fit isn't right, we'll send a free replacement size — keep the original, 30 days.

Sources and Method

Mid-thigh figures come from the CDC's National Center for Health Statistics: McDowell MA, Fryar CD, Ogden CL, Flegal KM, Anthropometric Reference Data for Children and Adults: United States, 2003–2006, National Health Statistics Reports No. 10 (2008), Table 40. NHANES measured mid-thigh circumference on standing adults, with the tape around the middle of the thigh. Pregnant women were excluded.

Upper-thigh and above-the-knee figures come from the 2012 U.S. Army Anthropometric Survey (ANSUR II) of 1,986 women. Army personnel are younger and more physically active than the general population, so the civilian upper-thigh average is likely higher.

Limitations: NHANES last measured thigh circumference in the 2005–2006 survey cycle, so these are the most recent national figures available. Average body weight for U.S. women has risen since then, from 164.7 lb in 2003–2006 to 171.8 lb in 2021–2023, according to the CDC, so today's averages are likely somewhat larger. Inches are converted from centimeters and rounded to one decimal place.

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