This light blue background pattern is quite pleasing to the eye, it consists of a tiny rough grid pattern, which is seamless by design. That's it, if you like the color, you can use this seamless pattern in a web design without making any further modifications to it.
Source V. Hartikainen
"Beige Stone", Tileable Texture.
Source V. Hartikainen
Abstract Tiled Background Extended 8
Source GDJ
I love cream! 50x50px and lovely in all the good ways.
Source Thomas Myrman
A slightly grainy paper pattern with small horizontal and vertical strokes.
Source Atle Mo
From an image on opengameart.org shared by rubberduck.
Source Firkin
Tweed is back in style – you heard it here first. Also, the @2X version here is great!
Source Simon Leo
Abstract Geometric Monochrome Pattern Prismatic No Background
Source GDJ
A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-I.
Source Firkin
Lovely light gray floral motif with some subtle shades.
Source GraphicsWall
A browner version of the original weathered fence texture.
Source Firkin
Prismatic Geometric Tessellation Pattern 2 No Background
Source GDJ
Prismatic Triangular Background Design Mark II 5
Source GDJ
A repeating background of beige (or is it more vanilla yellow) textured stripes. One more background with stripes.
Source V. Hartikainen
A seamless background drawn in Paint.net and vectorised with Vector Magic. The starting point was a photograph of drinking straws from Pixabay.
Source Firkin
Zero CC tileable ground (#2) cracked, crackled texture, made by me. CC0
Source Sojan Janso
Dark, square, clean and tidy. What more can you ask for?
Source Jaromír Kavan
Bigger is better, right? So here you have some large carbon fiber.
Source Factorio.us Collective
From a drawing in 'Gately's World's Progress', Charles Beale, 1886.
Source Firkin
Remixed from a drawing in 'Analecta Eboracensia', Thomas Widdrington, 1897.
Source Firkin
Imagine you zoomed in 1000X on some fabric. But then it turned out to be a skeleton!
Source Angelica
It almost looks a bit blurry, but then again, so are fishes.
Source Petr Šulc