Dark blue concrete wall with some small dust spots.
Source Atle Mo
Black brick wall pattern. Brick your site up!
Source Alex Parker
The classic subtle pattern. Sort of wall/brick looking. Or moon-looking?
Source Joel Klein
Alternative colour scheme. Not a pattern for fabrics, but one produced from a jpg of a stack of fabric items that was posted on Pixabay. The tile that this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
An emulated “transparent” background pattern, like that of all kinds of computer graphics software.
Source AdamStanislav
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Looks a bit like concrete with subtle specks spread around the pattern.
Source Mladjan Antic
Prismatic 3D Isometric Tessellation Pattern 6
Source GDJ
This texture looks like old leather. It should look great as a background on web pages.
Source V. Hartikainen
Background Wall, Art Abstract, Block Well & CC0 texture.
Source Ractapopulous
Prismatic Hypnotic Pattern 2 No Background
Source GDJ
A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
A pattern derived from repeating unit cells each derived from part of a fractal rendering in paint.net.
Source Firkin
Formed from a tile based on a drawing from 'Viaggi d'un artista nell'America Meridionale', Guido Boggiani, 1895.
Source Firkin
Black & white version of a pattern that came out of playing with the 'light rays' plug-in for Paint.net
Source Firkin
This was formed by distorting an image of a background on Pixabay.
Source Firkin
This background has abstract texture with some similarities to wood.
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
Thin lines, noise and texture creates this crisp dark denim pattern.
Source Marco Slooten