Manual:Reduce size of the installation

A MediaWiki installation's size is more than 40 MB, but you can reduce it to less than 10 MB.

If you are only using certain languages, you can delete about 30 MB of files in PHP language files in languages/messages/ . For instance, if you are only using English, you can delete everything but the file that start with MessagesEn.
You can also free up about 1 MB by deleting skins you don't use. Set a default skin using $wgDefaultSkin. Then, if you are using the Simple skin, go into skins/ and delete everything but Simple.php, Simple.deps.php, and simple/. This frees up about 1 MB.
You can free up about 500 KB by deleting the HISTORY, RELEASE-NOTES, COPYING, UPGRADE files.

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