Dark Wall #817
Dark CC BY-SA 3.0Just to prove my point, here is a slightly modified dark version.
Source Atle Mo
More Textures
Tessellation 15 (colour 3) #2220
Red CC 0The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Cardboard Flat@2X #962
Gray CC BY-SA 3.0Not a flat you live inside, like in the UK – but a flat piece of cardboard.
Source Appleshadow
Fabric pattern (colour 6) #2397
Fabric CC 0Alternative 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
Seamless Pink Background #1220
Red CC BY-SA 3.0Here's a new background image for websites with a seamless pink texture. It should look beautiful with website themes where light pink background is needed. The background is seamless, therefore it should be used as a tiled background.
Source V. Hartikainen
Wall & Red #1363
Wall CC 0Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Prismatic Snowflakes Pattern 3 No Background #413
Light CC 0Prismatic Snowflakes Pattern 3 No Background
Source GDJ
Texturetastic Gray@2X #616
Paper CC BY-SA 3.0This ladies and gentlemen, is texturetastic! Love it.
Source Adam Pickering
Transparent Square Tiles@2X #299
Grid CC BY-SA 3.0The first pattern on here using opacity. Try it on a site with a colored background, or even using mixed colors.
Source Nathan Spady
White Brushed@2X #1184
Wall CC BY-SA 3.0Brushed aluminum, in a bright gray version. Lovely 2X as well.
Source Andre Schouten
Spiral pattern 3 #1934
Dark CC 0From a drawing in 'Danmarks Riges Historie af J. Steenstrup, Kr. Erslev, A. Heise, V. Mollerup, J. A. Fridericia, E. Holm, A. D. Jørgensen', 1897.
Source Firkin
Prismatic Curved Diamond Pattern 6 No Background #545
Dark CC 0Prismatic Curved Diamond Pattern 6 No Background
Source GDJ
Inspiration Geometry@2X #1176
Unknow CC BY-SA 3.0This one is rather fun and playful. The 2X could be used at 1X too!
Source Welsley
Flying swan pattern #1979
Blue CC 0Remixed from a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Dark Blue Gray Wallpaper Texture #901
Stripes CC BY-SA 3.0This seamless background image should look nice on websites. It has a dark blue gray texture with vertical stripes, it tiles seamlessly and, like all of the background images here, it's free. So, if you like it, take it!
Source V. Hartikainen
Prismatic Abstract Geometric Background #269
Noise CC 0Prismatic Abstract Geometric Background derived from an image on Pixabay.
Source GDJ
Grass #1286
Unknow CC 0Zero CC tileable dry grass texture, photographed and made by me. CC0
Source Sojan Janso
Seamless Texture of Wood Planks #880
Wood CC BY-SA 3.0Here's an yet another background for websites, with a seamless texture of wood planks this time.
Source V. Hartikainen
Decorative divider 232 #2148
Dark CC 0From 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 215 (colour 2) #2370
Blue CC 0A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
Prismatic Polka Dots Mark II 3 No Background@2X #535
Noise CC 0Prismatic Polka Dots Mark II 3 No Background
Source GDJ
Background pattern 313 #1858
Dark CC 0Background pattern originally a PNG drawn in Paint.net
Source Firkin