Looks like a technical drawing board: small squares forming a nice grid.
Source We Are Pixel8
A seamless paper background colored in pale yellow.
Source V. Hartikainen
I took the liberty of using Dmitry’s pattern and made a version without perforation.
Source Atle Mo
Light gray grunge wall with a nice texture overlay.
Source Adam Anlauf
The perfect pattern for all your blogs about type, or type-related matters.
Source Atle Mo
Love me some light mesh on a Monday. Sharp.
Source Wilmotte Bastien
Small dots with minor circles spread across to form a nice mosaic.
Source John Burks
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
Colourful background achieved with gradient fills.
Source Firkin
Seamless Background For Websites. It has a texture similar to cork-board.
Source V. Hartikainen
You guessed it – looks a bit like cloth.
Source Peax Webdesign
This is a grid, only it’s noisy. You know. Reminds you of those printed grids you draw on.
Source Vectorpile
A seamless background of warped stripes on paper.
Source V. Hartikainen
Abstract Geometric Monochrome Pattern Prismatic No Background
Source GDJ
The rectangular tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Prismatic Groovy Concentric Background 5
Source GDJ
Prismatic Geometric Tessellation Pattern 4 No Background
Source GDJ
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin