As more people gain exposure to raw denim from brands all over the world, we’ve been hearing a lot of questions that pertain to not just what unsanforized denim is but what actually is the difference between unsanforized denim and sanforized denim outside of the way they’re treated.

It’s a question that gets a pretty wide variety of responses from both unsanforized denim fans and detractors. With more attention being turned to this subject and information being a bit fragmented across the many forums, we thought it was time to dive a bit more into unsanforized denim and present information about that will hopefully help determine whether or not unsanforized denim is for you.

What Does Unsanforized Mean?

To start, it’s important to set a baseline of what sanforization is. Sanforization is a process designed to eliminate the amount a fabric shrinks when washed. After coming off the loom, the fabric is fed through a sanforization machine which uses a series of rollers, moisture, and heat to stretch, shrink, and stabilize the fabric. Many times this is referred to as pre-shrunk and a vast majority of denim on the market these days is sanforized. Shrinkage with sanforized denim is typically limited to less than 1%. Check out our full guide for more info on the sanforization process.

With that said, unsanforized denim is simply fabric that did not go through the sanforization process and therefore will shrink when washed or soaked. Unsanforized denim can also be referred to as “shrink-to-fit”or STF, which is a term used by Levi’s for their unsanforized jeans. Occasionally the term “loomstate“, which means that the fabric is unaltered and untreated after being woven, will be used to describe unsanforized denim.

The general rule with unsanforized denim is that you should give it a soak for a certain amount of time to allow it to shrink before you start wearing the jeans. This is why brands and stores will suggest sizing up one or two sizes with unsanforized denim. Sizing up will allow the denim to shrink to the right size when soaked for the first time.

What Makes Unsanforized Denim Desirable?

Whether or not unsanforized denim is “better” is completely subjective but we’ll dive a little bit deeper on how unsanforized and sanforized denim differ from one another other than the shrinking aspect. As mentioned before, the sanforizing process applies heat, moisture, and pressure to the fabric to shrink and stretch it repeatedly.

While this process is very effective in removing most of the shrinkage from the fabric, it can also flatten the denim and cause it to lose some of its rougher characteristics. Some mills will even singe the hairs off the denim and mercerize it to achieve a more uniform and lustrous look. The result often times is a smoother looking denim that is ready to wear right away and still can fade very well with wear but ultimately, the fabric does lose some of its character.

Unsanforized and loomstate denim retains all the qualities that are caused by the type of cotton being used, how the yarn is spun, dyed, and how the yarns are woven together to make the fabric. These different characteristics are accentuated as the denim ages and result in very unique wear marks and fades. Often times with unsanforized denim, the jeans will still fade well even with less time in between washes which is a result of the denim not going through any treatment off the loom.

With that in mind, it’s important to note that not all unsanforized denim fabrics have the same characteristics and fading properties as that is largely dependent on the mill that creates the denim fabric. In general, most mills that offer unsanforized denim are very specliazed in creating high quality textiles and many work with each individual company to create denim with certain characteristics that become unique calling cards for each brand. This is why brands such as The Flat Head, Pure Blue Japan, and Samurai have denim fabrics that while are all unsanforized, will vary drastically from one another.

The idea of unsanforized denim is great especially for those looking for more unique and distinctive fabrics but it’s not without some drawbacks. Because the denim can shrink anywhere from 1-2 sizes, there is a level of uncertainty when it comes to what size to choose.

The water temperature, duration of the initial wash or soak, and even the amount of agitation you apply to the denim during a soak can affect how much the denim shrinks. To help eliminate some confusion, stores like Self Edge, Blue in Green, Blue Owl, and Rivet and Hide have a knowledgeable staff that can offer sound advice on how to size and shrink the jeans they sill. And those willing to take the time, there is a large amount of information on forums such as Styleforum and Superfuture that can shed light on how to best size.

But even with the information available, there’s still a chance of the denim will shrink differently from expected not only from the initial soak/wash but also after the first wash after wearing. Without sounding overdramatic, it’s a try-at-your-own-risk situation especially if you lack experience with it. Many Japanese brands offer unsanforized jeans once washed to shrink the fabric in order to alleviate some of the uncertainty. In these cases, there will be no need to soak the jean again since the brand or store has taken care of that already.

It can be argued that unsanforized denim is desirable not just because of the fact that it’s unsanforized but also because the brands and mills that offer them are some of the best in the industry. Any denim coming from these companies, whether it’s sanforized or not, would be of the highest quality. For many people, the efforts needed to size and wash unsanforized denim properly is actually a desired additional step in personalizing the jeans and well worth being able to wear denim made by these well respected brands. It’s not to say though that sanforized denim is necessarily a lesser quality fabric.

If you take a look at our Fade Friday section, you’ll see some great examples of beautifully worn-in jeans from brands like 3Sixteen, Rogue Territory, and Tellason who use high quality and well-made sanforized denim from mills in Japan and America that have plenty of character and ages well.

In the end, whether it’s unsanforized or sanforized denim, it’s important to remember that all the fuss about denim is all for nothing if you’re not wearing it so do your research on the brands, ask questions, make a choice, and start wearing your jeans.