This one takes you back to math class. Classic mathematic board underlay.
Source Josh Green
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
You know I love paper patterns. Here is one from Stephen. Say thank you!
Source Stephen Gilbert
Vector version of a png that was uploaded to Pixabay by pencilparker
Source Firkin
From a drawing in 'Chambéry à la fin du XIVe siècle', Timoleon Chapperon, 1863.
Source Firkin
A seamless pattern created from a square tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
More bright luxury. This is a bit larger than fancy deboss, and with a bit more noise.
Source Viszt Péter
You don’t see many mid-tone patterns here, but this one is nice.
Source Joel Klein
Same classic 45-degree pattern, dark version.
Source Luke McDonald
A web texture of brown canvas. Will look great, when used in dark web designs.
Source V. Hartikainen
A free repetitive background with a dark concrete wall like texture. This one may be used in dark web site designs.
Source V. Hartikainen
This tiled background comes in red and consists of tiles that look like gemstones. It is more for blogs or social profiles, I think.
Source V. Hartikainen
The first pattern on here using opacity. Try it on a site with a colored background, or even using mixed colors.
Source Nathan Spady
It almost looks a bit blurry, but then again, so are fishes.
Source Petr Šulc
A bit like some carbon, or knitted netting if you will.
Source Anna Litvinuk
Dead simple but beautiful horizontal line pattern.
Source Fabian Schultz
From a drawing in 'Cowdray: the history of a great English House', Julia Roundell, 1884.
Source Firkin
Not even 1kb, but very stylish. Gray thin lines.
Source Struck Axiom
A light gray fabric pattern with faded vertical stripes.
Source V. Hartikainen
Prismatic Curved Diamond Pattern No Background
Source GDJ
As simple and subtle as it gets. But sometimes that’s just what you want.
Source Designova
Prismatic Abstract Geometric Background 2 No Black
Source GDJ
Remixed from a drawing in 'Maidenhood; or, the Verge of the Stream', Laura Jewry, 1876.
Source Firkin
Geometric triangles seem to be quite hot these days.
Source Pixeden
It looks like a polished stone surface to me. Download it for free, as always.
Source V. Hartikainen