Fish Pattern Background #233
 Noise  CC 0

From PDP.

Source GDJ

 More Textures
Background pattern 117 #524
 Noise  CC 0

A seamless pattern drawn originally in Paint.net by distorting a slice of background pattern 116 and copying the resulting triangle numerous times.

Source Firkin

Background pattern 339 (colour) #1708
 Yellow  CC 0

The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i

Source Firkin

Prismatic Geometric Pattern Variation 2 With Background@2X #472
 Noise  CC 0

Prismatic Geometric Pattern Variation 2 With Background

Source GDJ

Prismatic Abstract Geometric Background 3 #270
 Noise  CC BY-SA 3.0

Prismatic Abstract Geometric Background 3

Source GDJ

Background pattern 258 (colour) #2134
 Red  CC 0

Remixed from a design on Pixabay. To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i.

Source Firkin

Background pattern 15 #201
 Dark  CC 0

A seamless pattern the starting point for which was a 'colour modulo' texture in Paint.net.

Source Firkin

Decorative divider 229 #2151
 Dark  CC 0

From a design found in 'History of the Virginia Company of London; with letters to and from the first Colony, never before printed', Edward Neill, 1869.

Source Firkin

Background pattern 254 #2144
 Dark  CC 0

To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i.

Source Firkin

Light Blue Background Pattern #1161
 Grid  CC BY-SA 3.0

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

Black Scales #191
 Dark  CC BY-SA 3.0

Same as Silver Scales, but in black. Turn your site into a dragon with this great scale pattern.

Source Alex Parker

Triangles pattern #2408
 Brown  CC 0

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

Abstract Arbitrary Geometric Background #497
 Noise  CC 0

Abstract Arbitrary Geometric Background derived from an image on Pixabay.

Source GDJ

crissXcross@2X #112
 Dark  CC BY-SA 3.0

Dark pattern with some nice diagonal stitched lines crossing over.

Source Ashton