Looks like a technical drawing board: small squares forming a nice grid.
Source We Are Pixel8
A free repetitive background with a dark concrete wall like texture. This one may be used in dark web site designs.
Source V. Hartikainen
One more updated pattern. Not really carbon fiber, but it’s the most popular pattern, so I’ll give you an extra choice.
Source Atle Mo
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Sounds like something from World of Warcraft. Has to be good.
Source Tony Kinard
Vector version of a png that was uploaded to Pixabay by pencilparker
Source Firkin
Pattern produced in Paint.net using the Vibrato plug-in.
Source Firkin
Dark, crisp and subtle. Tiny black lines on top of some noise.
Source Wilmotte Bastien
The texture of this background image has some similarities with leather, and it's colored in a dark brown color. So, if you are looking for a dark brown background image for your website, this may be an option for you.
Source V. Hartikainen
Adapted from a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Abstract Tiled Background Extended 8
Source GDJ
Light square grid pattern, great for a “DIY projects” sort of website, maybe?
Source Rafael Almeida
Dead simple but beautiful horizontal line pattern.
Source Fabian Schultz
Remixed from a drawing in 'Hungary. A guide book. By several authors', 1890.
Source Firkin
This light yellow background pattern consists of an irregular pattern of spots. Here's a light background pattern with yellowish tint.
Source V. Hartikainen
This one is amazing, truly original. Go use it!
Source Viahorizon
Fabric-ish patterns are close to my heart. French Stucco to the rescue.
Source Christopher Buecheler
A pale orange background pattern with glossy groove stripes.
Source V. Hartikainen
You know I love paper patterns. Here is one from Stephen. Say thank you!
Source Stephen Gilbert
Tiny little fibers making a soft and sweet look.
Source Badhon Ebrahim