A seamless pattern the unit cell for which can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
A smooth mid-tone gray, or low contrast if you will, linen pattern.
Source Jordan Pittman
Derived from an image that was uploaded to Pixabay by Darkmoon1968
Source Firkin
Detailed but still subtle and quite original. Lovely gray shades.
Source Kim Ruddock
A simple circle. That’s all it takes. This one is even transparent, for those who like that.
Source Saqib
The classic 45-degree diagonal line pattern, done right.
Source Jorick van Hees
Prismatic Curved Diamond Pattern No Background
Source GDJ
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
Derived from an image that was uploaded to Pixabay by Kaz
Source Firkin
Bright gray tones with a hint of some metal surface.
Source Hendrik Lammers
A seamless background pattern of dark brown wood planks.
Source V. Hartikainen
Thin lines, noise and texture creates this crisp dark denim pattern.
Source Marco Slooten
This is a hot one. Small, sharp and unique.
Source GraphicsWall
A dark gray, sandy pattern with small light dots, and some angled strokes.
Source Atle Mo
Seamless SVG vector and JPG backgrounds with faded diagonal stripes. The colors are editable.
Source V. Hartikainen
Remixed from a drawing in 'Maidenhood; or, the Verge of the Stream', Laura Jewry, 1876.
Source Firkin
Abstract Arbitrary Geometric Background derived from an image on Pixabay.
Source GDJ
Zero CC tileable wood texture, made by me procedurally in Neo Texture Edit.
Source Sojan Janso
Prismatic Abstract Background Design
Source GDJ
This is the remix of "polka dot seamless pattern".The image depicts polka dot seamless pattern.
Source Yamachem
Prismatic Isometric Cube Wireframe Pattern No Background
Source GDJ
From a drawing in 'In an Enchanted Island', William Mallock, 1892.
Source Firkin
A bit simplified version. Although it could be edited out to be simpler. Anyway, this time the tiling is converted to a pattern fill -which is using clipping for the tile's edges.
Source Lazur URH