The first pattern on here using opacity. Try it on a site with a colored background, or even using mixed colors.
Source Nathan Spady
A seamless pattern recreated from an image on Pixabay. It is reminiscent of parquet flooring and is formed from a square tile, which can be recovered in Inkscape by selecting the ungrouped rectangle and using shift-alt-I together.
Source Firkin
Retro Circles Background 4 No Black
Source GDJ
Abstract Stars Geometric Pattern Prismatic No Background
Source GDJ
Alternative colour scheme. Not a pattern for fabrics, but one produced from a jpg of a stack of fabric items that was posted on Pixabay. The tile that this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Formed by distorting a JPG from PublicDomainPictures
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Sharp diamond pattern. A small 24x18px tile.
Source Tom Neal
Small dots with minor circles spread across to form a nice mosaic.
Source John Burks
Prismatic Abstract Geometric Background 4
Source GDJ
A free seamless background pattern for use on websites.
Source V. Hartikainen
Vector version of a png that was uploaded to Pixabay by pencilparker
Source Firkin
You know I’m a sucker for these. Well-crafted paper pattern.
Source Mihaela Hinayon
A seamless pattern the unit cell for which can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Prismatic Isometric Cube Extra Pattern No Background
Source GDJ
Derived from a PNG that was uploaded to Pixabay by nutkitten
Source Firkin
Everyone loves a diamond, right? Make your site sparkle.
Source AJ Troxell
The tile this is based on can be retrieved by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Here's a new gray "fabric" pattern. Use it as backgrounds for websites or for other purposes.
Source V. Hartikainen
Prismatic Curved Diamond Pattern 8 No Background
Source GDJ
A very slick dark rubber grip pattern, sort of like the grip on a camera.
Source Sinisha
From a drawing in 'Navigations de Alouys de Cademoste.-La Navigation du Capitaine Pierre Sintre', Alvise da ca da Mosto, 1895.
Source Firkin
An alternative colour scheme to the original seamless pattern.
Source Firkin
A beautiful dark padded pattern, like an old classic sofa.
Source Chris Baldie
The green fibers pattern will work very well in grayscale as well.
Source Matteo Di Capua