You finally found them: the perfect pair of jeans. They fit like they were made for you. Then, you wash them for the first time, and they come out a size too small.

Denim jeans shrink¹ because they are made of cotton, a natural fiber. During the manufacturing process, these fibers are stretched and put under tension. When you wash them, especially with heat and water, this tension is released, and the fibers relax back to their shorter, natural state.

In my 20-plus years of running a denim factory, shrinkage is one of the biggest factors we have to manage. We deal with it on a massive scale. We stretch, steam, and treat the fabric to control exactly how much it will shrink later on. The reality is that all 100% cotton denim has the potential to shrink.

It’s the nature of the fiber. But understanding why it happens is the first step to controlling it. What we do in the factory can teach you how to care for your jeans at home.

How do I stop my jeans from shrinking?

You're standing in front of your washing machine, holding your favorite jeans. You feel anxious, worried that this wash will be the one that ruins their perfect fit forever.

The best way to stop your jeans from shrinking is to wash them as little as possible, always use cold water on a gentle cycle², and never put them in a high-heat tumble dryer. Opting for hang-drying is the single most effective step you can take.

Heat is the number one enemy of a perfect fit. In my factory, we use heat and steam in a very controlled way to force the denim to shrink before it's even sewn.

This process is called sanforization³. At home, uncontrolled heat from your washer and dryer does the same thing, but in a way you can't predict.

The hot water and the tumbling action of a hot dryer both relax the cotton fibers, causing them to contract. To prevent this, you must change your laundry habits.

Always turn your jeans inside out to protect the color, use the gentlest cycle your machine has, and select the cold water setting. Then, when they are done, pull them from the machine, give them a good shake, and hang them up to dry away from direct sunlight.

How to control denim shrinkage?

You understand that some shrinkage is inevitable, especially with new jeans. But you feel like it's a lottery, and you want to feel more in control of the outcome.

To control denim shrinkage, you must first know what kind of denim you have. For most jeans, which are "sanforized" or pre-shrunk, washing cold and air-drying is enough. For "unsanforized" raw denim, a controlled initial soak is necessary to manage the shrinkage predictably.

In the denim world, we categorize fabrics into two main types based on how they are treated for shrinkage. Understanding which type you own is the key to control.

1. Sanforized Denim: This is what 99% of people buy. The fabric has been pre-shrunk at the mill. We do this with a large machine that uses steam and rollers to compact the fibers. This process removes most of the potential shrinkage before the jeans are ever made. So, with these jeans, your job is just prevention: use cold water and avoid the dryer.
2. Unsanforized Denim: This is also known as "loomstate" or "shrink-to-fit" denim, and it's for denim enthusiasts. This fabric has not been treated at all. It will shrink a lot, sometimes up to 10%, which can be two full sizes. For these, the shrinkage isn't something to prevent; it's a feature you control with a deliberate first soak to make the jeans conform to your body.

A Quick Comparison

Denim Type	What It Is	How to Control Shrinkage	Expected Shrinkage
Sanforized	The fabric is pre-shrunk at the factory.	Wash cold, hang dry.	Minimal (1-3%)
Unsanforized	The fabric is completely untreated.	A planned initial soak before wearing.	Significant (7-10%+)

Can you unshrink denim?

The worst has happened. Your jeans came out of the laundry and they are now uncomfortably tight. You're thinking about giving them away, mourning the loss of a perfectly broken-in pair.

Yes, you can often unshrink denim⁴ that has become too tight. The best method is to soak the jeans in lukewarm water mixed with hair conditioner. This relaxes the cotton fibers, making them pliable enough to be gently stretched back out.

This trick really works, and the science behind it is quite simple. Cotton fibers are like your own hair. The hair conditioner⁵ contains compounds that coat and lubricate these fibers, making them relax and loosen their tight, shrunken weave.

It won't perform miracles on jeans that have shrunk three sizes, but it can absolutely save a pair that has become just a little too snug.

Here's the step-by-step process:

1. Fill a tub or sink with lukewarm—not hot—water.
2. Add a generous tablespoon of hair conditioner or baby shampoo and mix it in.
3. Submerge your jeans and let them soak for about 30 minutes.
4. Gently squeeze the water out, but do not rinse them.
5. Lay the damp jeans on a large, dry towel.
6. While they are still damp, gently pull and stretch the parts that need it—the waist, the thighs, the length. You can also put them on while they are damp and move around a bit to help them mold to your body.
7. Let them air dry completely.

Does denim shrink every time you wash it?

You've survived the first wash, and the jeans still fit. But now you have a new worry. Will they continue to shrink a little bit more with every single wash?

No, denim does not shrink significantly every time you wash it. The vast majority of shrinkage occurs during the very first wash and dry cycle. Subsequent washes in cold water will cause minimal, almost unnoticeable changes in size.

Think of that first wash as a one-time event. This is when the cotton fibers⁶, which have been under tension since the day they were woven, finally get the chance to fully relax.

This is where the major size change happens. After that initial "settling in," the fabric reaches a more stable state. Of course, if you throw them in a hot dryer, the fibers will temporarily tighten up, making the jeans feel snug when you first put them on.

But this is not permanent shrinkage. It's a temporary contraction that will relax and stretch back out after an hour or two of wear. As long as you continue to wash your jeans in cold water and preferably air dry them, you do not need to worry about them getting progressively smaller over time.

Conclusion

Shrinkage is a natural part of cotton denim, but it is not something to fear. By understanding your denim and using cold water and air drying, you can easily control it.

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