A seamless pattern that includes the original tile (go to Objects / Pattern / Pattern To Objects in Inkscape's menu to extract it).
Source GDJ
Coming in at 666x666px, this is an evil big pattern, but nice and soft at the same time.
Source Atle Mo
An abstract web texture of a polished blue stone (or does it look more like ice).
Source V. Hartikainen
A dark pattern made out of 3×3 circles and a 1px shadow. This works well as a carbon texture or background.
Source Atle Mo
Seamless Prismatic Quadrilateral Line Art Pattern No Background
Source GDJ
Remixed from a PNG that was uploaded to Pixabay by k_jprather
Source Firkin
Abstract Geometric Monochrome Pattern Prismatic No Background
Source GDJ
Prismatic Abstract Geometric Background 5 No Black
Source GDJ
This one needs to be used in small areas; you can see it repeat.
Source Luca
Paper pattern with small dust particles and 45-degree strokes.
Source Atle Mo
From a design in 'Storia del Palazzo Vecchio in Firenze', Aurelio Gotti, 1889.
Source Firkin
Bright gray tones with a hint of some metal surface.
Source Hendrik Lammers
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
ZeroCC tileabel stone granite texture, edited from pixabay. CC0
Source Sojan Janso
A seamless pattern formed from a square tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
As simple and subtle as it gets. But sometimes that’s just what you want.
Source Designova
A large (588x375px) sand-colored pattern for your ever-growing collection. Shrink at will.
Source Alex Tapein
The rectangular tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
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
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
Dare I call this a «flat pattern»? Probably not.
Source Dax Kieran
A web texture of brown canvas. Will look great, when used in dark web designs.
Source V. Hartikainen