Very simple, very blu(e). Subtle and nice.
Source Seb Jachec
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Simple wide squares with a small indent. Fits all.
Source Petr Šulc.
This one is amazing, truly original. Go use it!
Source Viahorizon
This is so subtle you need to bring your magnifier!
Source Carlos Valdez
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Remixed from a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Formed by heavily distorting part of a an image of a fish uploaded to Pixabay by GLady
Source Firkin
Semi-light fabric pattern made out of random pixels in shades of gray.
Source Atle Mo
Little x’es, noise and all the stuff you like. Dark like a Monday, with a hint of blue.
Source Tom McArdle
A seamless pattern formed from background pattern 102
Source Firkin
Looks a bit like concrete with subtle specks spread around the pattern.
Source Mladjan Antic
The texture of this background image has some similarities with leather, and it's colored in a dark brown color. So, if you are looking for a dark brown background image for your website, this may be an option for you.
Source V. Hartikainen
Remixed from an image on Pixabay uploaded by Prawny
Source Firkin
This is a hot one. Small, sharp and unique.
Source GraphicsWall
A version without colours blended together to give a different look.
Source Firkin
Did some testing with Repper Pro tonight, and this gray mid-tone pattern came out.
Source Atle Mo
Prismatic Triangular Background Design Mark II 5
Source GDJ
Scanned some rice paper and tiled it up for you. Enjoy.
Source Atle Mo
A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
Fabric-ish patterns are close to my heart. French Stucco to the rescue.
Source Christopher Buecheler
New paper pattern with a slightly organic feel to it, using some thin threads.
Source Atle Mo