Using a repeating image for your Tumblr background often makes your blog more interesting and eye-catching. If your theme doesn't have a tiling option, you can make your image repeat in one of two ways. The easiest method is to add a single line of code to your blog's custom CSS field. This entry overrides your theme and creates a tiled background. You can also edit your theme directly to make the change. In either case, you must start with a background image small enough for tiling -- Tumblr won't automatically reduce large images for tiling.

The Easy Fix

Step 1

Sign in to Tumblr and click "Customize" on your dashboard to access your theme settings.

Step 2

Click "Advanced Options" at the bottom of the Customize pane, and enter the following line of code to the Add Custom CSS field:

body {background-repeat:repeat;}

Step 3

Click "Save," click the back arrow, and then click "Exit" to return to your dashboard.

The Harder Method

Step 1

Click "Customize" on your dashboard, and then click "Edit HTML" to open your theme's HTML code. This code controls the layout and appearance of your blog.

Step 2

Go to the beginning of the style sheet section of code. You can find the start of the style sheet by pressing "Ctrl-F" and searching for "<style type="text/css">" (without the outside quotes).

Step 3

Find the first line of code that looks similar to either one of these examples (the line in your theme may look slightly different):

background-repeat: no-repeat; background: url('{image:Background}') no-repeat;

Step 4

Replace "no-repeat" with "repeat".

Step 5

Click "Update Preview" to see if the change worked. If you see a tiled background in the preview screen, click "Save." Otherwise, undo the change and try again on the next line that includes the "no-repeat" attribute.