A heavy hitter at 400x400px, but lovely still.
Source Breezi
Prepared mostly as a raster in Paint.net and vectorised.
Source Firkin
Prismatic Hexagonalist Pattern No Background
Source GDJ
An alternative colour scheme to the original seamless pattern.
Source Firkin
Nice little grid. Would work great as a base on top of some other patterns.
Source Arno Gregorian
Dark squares with some virus-looking dots in the grid.
Source Hugo Loning
A seamless background texture of old cardboard.
Source V. Hartikainen
Three shades of gray makes this pattern look like a small carbon fiber surface. Great readability even for small fonts.
Source Atle Mo
Feel free to download and use it, or see the rest of the dark background patterns that I have made. Anyway, I hope you will find something that you like.
Source V. Hartikainen
Zero CC tillable hard cover red book with X shape marks. Scanned and made by me.
Source Sojan Janso
Alternative colour scheme for the original floral pattern.
Source Firkin
A repeatable image with dark background and metal grid pattern.
Source V. Hartikainen
Textured Red Brown Plastic, Free Background Pattern. Although there's already enough plastic in our lives, let's bring it to the web too.)
Source V. Hartikainen
From a drawing in 'Studies for Stories', Jean Ingelow, 1864.
Source Firkin
A beautiful dark padded pattern, like an old classic sofa.
Source Chris Baldie
Little x’es, noise and all the stuff you like. Dark like a Monday, with a hint of blue.
Source Tom McArdle
Zero CC tileable seed texture, edited by me to be seamless from a Pixabay image. CC0
Source Sojan Janso
If you like it a bit trippy, this wave pattern might be for you.
Source Ian Soper
A background formed from an image of an old tile on the New York Metropolitan Museum of Art website. To get the base tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin