Known as a "dobby border," the woven strip of a towel is not just decorative -- it also has useful functions, according to textile manufacturers.

On March 13, 2025, an X user asked a question that had onlookers showering him with theories: What exactly is the purpose of those thin woven strips on towels?

The post had amassed more than 91 million views as of this writing.

"I'm convinced that it only exists to shrink and make it impossible to fold the towel nicely, causing you to buy another towel," the user wrote in a reply that garnered another 11 million views.

Social media users responded to the post with various jokes or theories. Posts with tens of thousands of likes suggested the woven strips help towels dry faster, make them easier to grip or improve their hold when they are pinned to clotheslines. Some posts insisted that the woven strip is called a "dobby weave" or "dobby border" and that it prevents fraying or other issues with a towel's structure.

It turns out the answer may be all of the above -- at least according to towel wholesalers Towel Hub and Direct Textile Store. "Known as a dobby border, this woven strip helps prevent fraying, improves absorbency, and gives towels a professional, polished look," Towel Hub wrote in a March 11, 2025, blog post. The towel manufacturer also said the design feature improves grip and increases the speed at which a towel dries.

"The woven strip helps maintain an even structure, preventing the edges from becoming too bulky," Towel Hub's blog post said. The strip keeps the towel lighter and speeds up drying by ensuring "moisture is evenly distributed throughout the towel's surface."

Towels with woven strips are also easier to handle when "drying off, folding or stacking" and less likely to stretch compared to towels without the feature, according to the post. The so-called dobby border is particularly important for businesses that use towels frequently and intensely, such as hotels or gyms, and clean them via industrial washing machines and heavy-duty detergents.

As for the X user's complaint about shrinking, the towel wholesaler wrote:

Not all dobby borders are created equal. A well-made woven strip should be tightly stitched and seamlessly integrated into the towel's design. Loose or thin strips can weaken over time, diminishing the towel's durability and overall lifespan.

A separate blog post by Direct Textile Store written in 2018 said there are actually two different types of woven strips: "dobby borders" and "cam borders." The latter are less decorative -- "just a straight line across, generally less than an inch thick, with no specific patterns or designs." However, both are used for similar reasons, according to the post.

Towel Hub, Direct Textile Store and other towel manufacturers and textile experts did not return inquiries about the woven strip's purpose as of this writing. This story will be updated if they do.