Our Complete Guide to Denim Terminology

October 2020

A denim background with the words, "Tailor Tutorials, Jen Sharkey"A denim background with the words, "Tailor Tutorials, Jen Sharkey"

Your favorite pair of jeans has a story to tell. Here, Levi’s® tailor Jen Sharkey decodes the fabrics, stitching, hardware, and tell-tale signs that make every piece special.


Warp and weft: The two basic components of woven fabrics. They refer to the positions of the threads on the loom and the way the fabric is positioned when it’s cut and sewn.

Warp: Lengthwise yarns that are held in tension on the loom while the weft yarns are drawn over and under, creating a weave. The warp is the yarn that travels vertically along the jeans you’re wearing.

Weft: Crosswise yarns inserted over and under the warp. The most basic weave pattern is a 1x1 pattern where the weft goes over one warp thread and under the next.

Denim square

Twill: A type of weave that creates a diagonal (or alternating diagonal) pattern on the fabric surface. Denim is a twill that travels at a consistent diagonal. Herringbone is a broken twill, which means the diagonal switches directions back and forth.

A square of denim with a seam
Denim Twills: The twill weave is part of why we see a front and back side to denim. The warp yarn (front) is usually dyed indigo while the weft yarn (back) is left undyed natural cotton. A traditional over three, under one weave pattern creates denim’s diagonal texture and is part of what makes it so strong and durable
Denim twills on jeans

Selvedge: Woven on traditional narrow-width shuttle looms to produce a signature self-finished, clean edge – thus the name “selvedge” from “self edge.” You can spot a pair of selvedge jeans by looking at the inside of the outseam. When you roll the pant leg, you’ll find a crisp fabric strip with a stripe down the middle. This artful, functional detail is what sets selvedge apart from the rest of the denim kingdom.

denim square with Selvedge

Denim weight: Denim is weighed in ounces per square yard.

  • Lightweight denim: less than 12 oz
  • Mid-weight denim: 12 to 16 oz
  • Heavyweight denim: 17 oz and more

With the introduction of stretch garments, jeans have skewed lighter weight. As a result, heavy denims are now specialty products beloved by collectors and hardcore denimheads.

Raw denim: This refers to unwashed, untreated denim. Most of the jeans you find in stores have gone through wash cycles or surface treatments that soften it for the wearer. Raw denim must be broken in by wearing. The pro move is to wear your raw denim over and over (for weeks, months, or even a full year) before washing it for the first time.

woman holding raw denim fabric

Slub: A slub (not to be confused with a schlub) is an uneven surface, usually in the form of a small bump or bulge. Slubs result from yarn irregularities in the weaving process. Washing can make slubs more pronounced. Some slubby fabrics are highly desirable for their texture and the way they look over time

A slub on denim

Stretch vs Non-Stretch: Non-stretch denim is usually made of 100% cotton yarns along both the warp and the weft. Stretch denim incorporates 1 to 3% elastane (also known as spandex or Lycra) into the weft yarns to allow the garment to stretch and recover as you move. This stretch is spun into the yarns before being woven into fabric.

jeans being stretched


Rivet: A rivet is a piece of metal hardware that helps to reinforce a garment. The first riveted work pants, known today as blue jeans, were patented on May 20, 1873 by Levi Strauss & Co. and Jacob Davis. The rivets on our 501® Jeans are made of copper and are designed to add strength to the pockets.

A rivet in jeans

Shank buttons: Shank buttons sit slightly away from the garment and are fastened on using a dye set that pierces the denim and clamps the back piece onto the front shank, holding it securely in place.

A shank button


Topstitching: Any stitching that sits on the outside of the garment and is visible when worn. Jeans traditionally have quite visible orange or gold topstitching, which is both decorative and structural.

Denim with topstitching

Felled seam: Topstitching works in tandem with the construction to form denim’s traditional double flat felled seam. In this seam, the edges of the fabric fold under one another and are hidden from view. The two rows of stitching that hold these folds in place also hold the seam flat, resulting in the flat felled seam. This construction adds strength to the garment as there are fewer edges exposed to fraying during wear.

Felled seam in jeans

Lockstitch: The top thread loops under the bottom thread with each stitch, locking it into place. This continuous locking makes the stitch strong, durable, and quite tedious to remove.

A lockstitch on the pocket of jeans

Chainstitch: A sewing technique in which a series of looped stitches form a chain-like pattern. Chain-stitched embroidery is often so realistic that it actually looks illustrated onto the fabric.

A chainstitch in jeans

Bartack: A series of tight zigzag stitches used to reinforce stress points. They provide strength and durability to belt loops and pocket corners. During World War II, Levi’s® used bartacks instead of rivets in an effort to conserve metal.

A bartack on jeans


Arcuate: The iconic back pocket stitching pattern used on all Levi’s® jeans.

Arcuate on the back of Levi's jeans

Red tab: The small cloth tab inserted on most Levi’s® garments. It signifies the quality and longevity of Levi’s® products and provides a quick way for our customers to identify their jeans among many competing products.

The red tab on the back of Levi's jeans


Fades and whiskers: With wear over time, the top layer of indigo dye sloughs off of the warp yarns, creating a fade. Fades (back-pocket wallet marks, for instance) can often tell a story about the person in the jeans. Whiskers are subtle horizontal lines found along the thighs and other wear points of jeans. They happen naturally over time, but to craft this finish, we sometimes draw lines on jeans with sandpaper before stonewashing them — creating a perfectly well-worn look from day one.

Fades and whiskers on jeans

Yoke: The section of a jean directly under the waistband, the yoke is where the fit happens. Shirts can have yokes, too. A typical western shirt features a stylized yoke on the upper front and back as well as distinct single (Barstow) and double (Sawtooth) yoke designs on the pockets.

A women pointing to the yoke on a pair of jeans

Inseam/outseam: The inseam is the stitching that runs along the inside of the leg. The outseam is the stitch line or seam that runs vertically along the outside of the leg.

the inseam on jeans

Rise: The distance from the crotch point (where all four fabric panels meet) to the top of the waistband. Rise determines where the pants sit on your body and can create or alter where your perceived waistline sits. High-rise jeans sit near or above your natural waist. Low-rise jeans sit on or below the top of your hips. Mid-rise is anything in between, usually a few inches below your belly button.

A woman holding jeans showing where the inseam on jeans

J-stitch: The stitch pattern used in constructing the fly on a pair of jeans (and many other styles of trousers). It is shaped like the letter J and is often double topstitched for reinforcement. J-stitches allow for the buttons to be hidden behind a continuous panel of denim.

someone pointing the j-stitch on jeans

5 Pocket Jean: The traditional construction style for jeans. The five pockets were originally the two back pockets, two main front pockets, and a smaller pocket set within the right-side front pocket. The small one was originally known as the "watch pocket," and is now commonly called a “coin pocket.” When people stop using coins (any day now) we'll find another name for it.

A woman holding jeans showing all the pockets on Levi jeans

For even more trivia and terminology, check out our complete Denim Dictionary.