This is a semi-dark pattern, sort of linen-y.
Source Sagive SEO
Nice little grid. Would work great as a base on top of some other patterns.
Source Arno Gregorian
Simple wide squares with a small indent. Fits all.
Source Petr Šulc.
Prismatic Groovy Concentric Background 2
Source GDJ
People seem to enjoy dark patterns, so here is one with some circles.
Source Atle Mo
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Dark wooden pattern, given the subtle treatment. based on texture from Cloaks.
A yellow tiled background... Blurriness, bokeh effect and rectangles pattern in one mix.
Source V. Hartikainen
A grayscale fabric pattern with vertical lines of stitch holes.
Source V. Hartikainen
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
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
The act or state of corrugating or of being corrugated, a wrinkle; fold; furrow; ridge.
Source Anna Litvinuk
The classic notebook paper with horizontal stripes.
Source Are Sundnes
Not even 1kb, but very stylish. Gray thin lines.
Source Struck Axiom
Prismatic Geometric Pattern Background No Black
Source GDJ
Here's a brown background pattern with subtle stripes. I hope you'll like the color. If not, feel free to change it using an image editor, if you know how of course. Personally, I'm using GIMP to create these backgrounds.
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
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso