How do jean sizes work?

Spoiler alert. They don't.

Jean sizing is worse than a box of chocolates. Not only do you never know what you're going to get, but when you do get it, there's no chocolate involved.

But we got this. I'll step you through a brief history of jean sizes, how to make sense of the chaos and find a pair of jeans that fit.

For those who only want the quick and dirty, here's the cheat sheet.

How Jean Sizes Work in the US

Your cheat sheet for making sense out of nonesense.

Tip #1

All jean sizing has a loose correlation to waist circumference.

Tip #2

If the jean size has only one number, that's the number that correlates to waist size. If the jean size has two numbers, the second represents the inseam. More on that later.

Example. If you find a pair of jeans that are a size 8, that's a reference to your waist. If you find a size 8/32, the former correlates with your waist size, the latter with the length of your inseam.

Tip #3

If the size listed:

  • involves only one number;
  • is less than 19;
  • and is even;

You're dealing with grown folk sizing. To approximate the waist size, add 22 to the size.

Example. A size 4 jean loosely corresponds to a 26 inch waist.

Tip #4

If the size listed:

  • involves only one number;
  • is less than 18;
  • and is odd;

You're dealing with teen sizing. Unfortunaely, there's not a simple way to convert the jean size to inches around your waist.

Tip #5

Take all of this with a gigantic grain of salt. There is no consensus or governing authority regarding sizing. The measurements are entirely at the manufacturers' discretion.

Table of Contents

Ready for a deep dive on jean sizing? Here's what in store.

GET CONTEXT What the hell happened? Why are jean sizes so unreliable?

CHART YOUR DESTINY Jeans size chart for all my visual sisters.

MEASURE THE MADNESS How to measure your waist and inseam for jeans.

SURVIVE THE JEAN JUNGLE How to make sense out of jean sizing chaos.

AVOID THESE HARD FAILS When shopping for jeans online, don't make these mistakes.

Get Context

What the hell happened? Why are jean sizes so unreliable?


The golden years as all clothing was custom-made. If you had any idea how to work a sewing machine. And the gumption to put on a pair o dungarees.


Introduction of Lady Levi’s® jean - the first jeans made for women. Game changer.

1934 - 1938

The rule of age-based sizing, Yep. Age. You're 16 years old? Well naturally, you're a size 16. But wait, it gets better. Guess how your pant size was deduced? From your bust measurement. Imagine how difficult it must have been to stay abreast of jean sizes. (I get one, damn it!)


The Works Progress Administration (WPA) along with the Department of Agriculture decided to tackle sizing after manufacturing firms discovered the combination of measuring women according to age and hooters was costing them an estimated $10 million in pocket change each year.

While the cause was worthy and impressive --- over 15,000 women were measured in 59 different places, the effort was flawed. Only white chicks were measured. And poor white chicks at that. Although the survey was paid and voluntary, only women lacking financial alternatives were willing to subject themselves to the prodding. The result? Sizing was significantly smaller than the national average.

Also of note, despite the aforementioned $10 million loss per year due to sizing based on bustlines, this survey still couldn't drop its original premise that all women have an hourglass figure. As result, this study still based sizing largly on breast size.

Leave it to men to find 59 different ways to poke boobs.


The Amazon of 20th century , Sears, Roebuck and Co., wasn't happy with the WPA results. Having the largest mail-order business in the universe, Sears petitioned the government for greater accuracy.

Working with the federal government and the National Bureau of Home Economics starging in the late 1940s, the National Bureau of Standards pubilshed the Commercial Standard in 1958.

Chart Your Destiny

Jeans size chart for all my visual sisters.

Measure the Madness

How to measure your waist, hips and inseam for jeans.

Measuring your body for jeans can sometimes seem more art than science. Although more brands are beginning to include measurements for hips, there's still a bit of guess work as there's lost of variability regarding thighs and calves.

But we work with the measurements we got. Here's a clear cut guide to getting closer to the perfect fit.


Waist measurements are always confusing. Some folks suggest measuring your waist based on where your belly button is. Others suggest measuring the smallest circumference around your waist. And still others suggest meauring where your tummy is widest. Which one is right?

The answer is none of 'em. The best place to measure your waist is based upon the rise of the jeans you'd like to buy.

  • If high-rise, you'll want to measure 4 - 5 inches above your crotch point.
  • If mid-rise, you'll want to measure 2 - 3 inches above your crotch point.
  • If low-rise, you'll want to measure 1 - 2 inches above your crotch point.

Want more details? (Like what the hell is a crotch point?) Check out my article, how to measure your waist for jeans.

Survive the Jean Jungle

How to make sense out of jean sizing chaos.

Avoid These Hard Fails

Common mistakes that can be sidestepped with a few simple precautions.

  • Assume they all size alike. Every brand, every company and every manufacturer has their own idea about sizing. Don't assume standardization. Study the brand specific sizing chart like the livelihood of your thighs depends on it.
  • Disregard the origin story. Don't assume that a 32 is a US 32. Check the label for the country of origin. And if in Europe, refer to the chart above. Each country in the EU maps to waist size differently.
  • Not inseam-inating. Don't take the inseam measurement for granted. Even if not listed on the size tag, each brand has a default measurement for length. Take heed.
  • Forgetting the body check. Body shape matters. Think about how sizing defaults for each brand are wired when considering which size to purchase.

You now know how jean sizing works.

And how it doesn't work. I wish you luck and an actual box of chocolates.

Have a favorite sizing hack? Please share the gospel below!