Inseam

How to Measure the Inseam on Jeans

Published on February 14, 2025

When it comes to buying jeans—especially online—getting the right inseam measurement is crucial for a proper fit. Whether you’re checking your size before ordering, comparing different brands, or preparing for hemming, measuring the inseam correctly ensures you won’t end up with jeans that are too short or too long.

In this guide, we’ll break down how to measure the inseam on jeans the right way, just like the professionals. Plus, watch our quick video tutorial featuring Williamsburg Garment Company’s own Maurice Malone, who walks you through the process step by step.

📏 What Is the Inseam on Jeans?

The inseam is the measurement from the crotch seam (where the inner thigh seams meet) down to the hem of the pant leg. It determines the length of your jeans and is one of the most important sizing details when shopping for denim.

🛠 Step-by-Step: How to Measure the Inseam on Jeans

Follow these steps to measure your inseam accurately:

1️⃣ Lay the Jeans Flat

Find a flat surface (like a table or the floor) to lay your jeans down.
Smooth out any wrinkles, but don’t stretch the fabric.

2️⃣ Start at the Center of the Crotch Seam

Place your measuring tape at the center of the crotch seam, between the two stitch lines of the flat-felled seam.
This is the center point of the flat-felled seams, which ensures an accurate starting position.

3️⃣ Follow the Natural Shape of the Leg

Extend the measuring tape down the inside of the leg, following the natural curve.
Avoid pulling the tape too tight or leaving slack—precision matters!

4️⃣ Measure to the Hem

Stop at the bottom edge of the hem and take note of the number.
This final measurement is your inseam length.

🚨 Common Mistakes to Avoid

🔴 Measuring in a straight line – The inseam follows the natural curve of the leg, so don’t measure at an angle or cut across the fabric.

🔴 Starting at the wrong point – Always measure from the center of the crotch seam, between the stitch lines, not from the seam line or a random point along the leg.

🔴 Ignoring fabric twist – Some jeans, especially washed or vintage styles, may have a slight twist. Follow the intended seam line, not any twisting caused by wear.

👖 Why Accurate Inseam Measurements Matter

If your jeans are too long or too short, it affects both comfort and style. Knowing your inseam helps when:
✅ Buying jeans online – Compare with the brand’s size chart to get the right fit.
✅ Altering your jeans – Get the perfect length when hemming.
✅ Finding the right cut – Different inseams work better for different styles (stacking, cuffing, or a clean break at the shoe).

⚠️ Don’t Assume the Inseam Length on the Tag Is Accurate

When you purchase a pair of jeans, it is highly likely that the inseam length on the tag is not correct. Most brands intentionally make their inseams longer than the labeled length, figuring it’s better to be longer than shorter or to allow for shrinkage after washing or alterations if needed. However, in some cases, brands may even produce inseams that are shorter than labeled—so always measure your jeans instead of trusting the tag.

⚠️ Be Careful When Ordering Hemming on Multiple Jeans

If you’re getting multiple pairs of jeans hemmed, avoid ordering the same inseam length across different styles without considering fit type and rise length.

Rise differences matter – Even if two jeans have the same waist measurement, a longer rise will result in an inseam that appears longer. Since both jeans sit at the same position on your body due to the identical waist measurement, the additional rise length means the hem will fall lower on your leg.
Waist opening affects inseam fit – The waist opening measurement generally determines where jeans sit on your body. For example, a larger waist measurement will sit lower on the hips compared to a smaller waist, even if the rise is the same. This lower placement causes the inseam to effectively be longer, as the jeans rest further down on your body.

These factors mean that jeans of the same labeled inseam can fit very differently based on their waist and rise measurements. To ensure consistency, always measure each pair individually before choosing a hemming length.

📌 Need Professional Denim Alterations?

At Williamsburg Garment Company, we specialize in professional denim hemming and alterations, ensuring your jeans fit perfectly—no matter the inseam length.

👉 Visit our site for expert hemming & alterations

Overlock and flat-felled seam types by highlighting the hem of a pair of jeans sewed with an overlocked inseam on the left and a flat-felled seam on the right. — This image explains the overlock and flat-felled seam types by highlighting the hem of a pair of jeans sewed with an overlocked inseam on the left and a flat-felled seam on the right.

101/Denim/What is?

Definition of inseam types: Overlock & flat-felled seams

Published on July 14, 2023

Jeans and pants are a part of our everyday lives, and there’s more to them than just the fabric. Have you ever thought about the seams? They play a big role in how your jeans and pants look, feel, and last.

Excluding tailored clothing which is generally a single lockstitch with merrow stitching or binding over the edges, the two main kinds of seams in jeans and similarly constructed pants are flat-felled and overlocked seams.

If you’re thinking about tailoring your jeans or pants (especially tapering) or just want to know more about fashion, it’s good to understand these seams. Why? Because each seam type comes with its own set of benefits and challenges that can significantly affect the alteration process, durability, and aesthetics.

Flat-felled vs. Overlocked seams

Flat-felled seams are the most common type of inseam construction on jeans and similarly constructed pants. They are created by folding the raw edges of the fabric over, and on themselves, then stitching them together. This creates a strong and durable seam that is also very flat and neat. These seams are celebrated for their durability, fray resistance, clean finish, and aesthetic value. Flat-felled seams are often used on high-quality jeans in the light-to-midweight fabric range but can be a problem with heavyweight or thick fabrics because of the multiple layers of folded fabrics required to sew through where seams meet and the fabric’s weight.

When it comes to sewing through multiple seams, manufacturers of heavyweight denim will use flat-felled seams at the seat, even though they must sew through 12 layers of fabric where the yoke and center seat seams meet, and avoid the flat-felled seam on the inseam, where 8 layers of fabric must be sewn through in the crotch, for several reasons.

First, in the seat area of jeans and similarly constructed pants, the flat-felled’s low profile, smoothness, and visual aesthetic have more value than an overlocked seam. Second, because of the shorter distance regarding sewing, errors can be more quickly corrected compared to the long distance at the inseam.

Some brands, such as Bravestar and a few others, will take on the massive challenge of producing heavyweight jeans with flat-felled inseams. Sewing flat-felled inseams of heavy jeans during tapering is tough in our experience, not because of the fabric’s thickness, but due to the weight and gravity pulling on the jeans while they hang under the off-the-arm sewing machine. The weight exerts a continual tug on the fabric, which the sewer is attempting to hold upward into the folder, which causes the fabric edges to turn over, to create flat-felled seams. Shorter sewing distances, such as the rear yoke and center seat seams, are not a problem. Longer sewing distances, such as the inseam, have three to four times the weight and force pulling the fabric down and out of the folder. As a result, every time the sewer adjusts their hand position while sewing, the fabric slips down, or lower in the folder, causing sewing problems. This is most certainly the most significant explanation for why factories prefer to produce heavyweight jeans with overlock inseams.

Overlock seams, also known as serged seams, are another common type of inseam construction. These are generally used on the insides of the garment. Overlock seams are created by an overlock machine, which stitches the seam, trims the seam allowance, and encases the edge of the fabric with thread, all in one step.

The overlocked seam is more valued at the inseam on heavyweight jeans because it’s easier to sew. Also, it does not create as much bulk where the seams meet in the crotch, where there is lots of movement, unlike the yoke area of the seat, which sits flat. Lastly, the more unsightly appearance of the overlock seam is not visible on the inseam unless the jeans are turned up at the hem.

While not as durable or aesthetically pleasing as flat-felled seams, overlock seams are quicker and more economical to produce. They also provide adequate fray resistance, which is particularly important on the raw edges of denim.

The Importance of seam type in Tapering Jeans and Pants

What does this have to do with getting your pants and jeans tapered? To begin with, the type of seam influences the method and difficulty of making an alteration. The vast majority of tailors will taper jeans and pants from the outseam to avoid the inseam because of a lack of equipment, knowledge, or both. This is not an option with selvedge clothing since it would damage the selvedge. Unless flared, or garments designed for curvy bodies, the shape of jeans and pants legs is typically drafted in the inseam, leaving the outseams mostly straight up to the hips. As a result, modifications should also be made to the inseam.

Tailoring flat-felled seams requires a feed-off-the-arm sewing machine to be done correctly, and in order to maintain the original construction. It also requires skill and knowledge of the construction techniques used on mass-produced read-to-wear garments, which often have very different rules than tailored clothing.

Overlock seams, on the other hand, are easier and faster to alter. An overlock machine, which is one of the more common types of sewing machines available in many types of tailoring establishments, can be used to cut and re-sew the seam. Most tailors will struggle with how to handle the top stitch that is sewn on top of overlocked seams. Without an off-the-arm machine, it’s impossible to sew a fresh top stitch from hem to hem in a single pass, without taking the garment apart. Because they can only sew so far up the leg, heading upward towards the crotch, they must either link a new top stitch to the previous one. Alternatively, they can open the outseams all the way to the hips in order to fit the jeans or pants through a flatbed machine, sewing around the inseam, in a single pass.

In Summary

Choosing to taper your jeans can give them a fresh lease of life, adapting them to changing trends or personal style preferences. But before you take them to a tailor, examine the inseam construction. Knowing whether you’re dealing with a flat-felled or overlocked seam will help you understand the complexity of the task and manage your expectations regarding cost, time, and final appearance. This way, you’ll ensure you’re making an informed decision about tailoring, helping your favorite denim remain a staple in your wardrobe for years to come.