What Is The Purpose Of Those Lines On Your Towels?

When looking at a towel, you may have wondered a few things, such as, "Why do I have to wash my towel when I only use it when I've literally just been cleaned?" and, "Huh, what the hell are those lines for?"

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The latter question has been discussed a lot earlier this year, after one X user posed it to the Internet. While some just used it as an opportunity to make wave-particle duality jokes, others were desperate for answers. 

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Some suggested it was a "face/butt delineation line", or else "racing stripes" to "make them dry faster".

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But the consensus amongst those demanding real answers was that it was likely something to do with strengthening the towel. This is indeed part of the answer.

The line is known as the "dobby border", and is there for a number of reasons, including to improve how absorbent the towel is, and prevent fraying over many uses and washes.

"Absorbency is one of the most important qualities of a good towel, but achieving the perfect balance between thickness and performance can be challenging," Towel Hub explains. "The woven strip helps maintain an even structure, preventing the edges from becoming too bulky. This ensures that the towel remains soft, lightweight, and easy to handle, making it more efficient for drying both the body and surfaces."

As well as practical purposes, they are there for a pleasing aesthetic.

"The woven strip at both ends of a towel serves multiple practical purposes, from preventing fraying to enhancing durability, improving absorbency, and adding an elegant finishing touch," Towel Hub adds. "This small but essential feature ensures that towels last longer, dry faster, and maintain a polished appearance, making them an excellent choice for both personal and commercial use."

With that mystery solved, perhaps we can move on to bigger puzzles, like dark energy or what screensavers are for.

An earlier version of this article was published in March 2025.