How to Reject File Extensions in Wget?

When downloading websites or bulk files using the wget command-line utility, you often want to avoid downloading specific types of files, such as heavy videos, images, or unwanted scripts. To achieve this, wget provides a dedicated reject flag that allows you to specify exactly which file extensions to skip during the download process. Managing your downloads this way saves both bandwidth and local storage space.

The Reject Flag: -R or --reject

To exclude certain file extensions, you use the -R (short form) or --reject (long form) flag. This flag tells wget to check the file extension of every resource it encounters and ignore any that match your specified list.

Basic Syntax

wget -R alternative,extension,list URL

Common Usage Examples

• Rejecting a single file type: If you want to download a directory but skip all PDF files, you would run:

wget -R pdf http://example.com/files/

• Rejecting multiple file types: You can exclude multiple extensions by separating them with a comma (and no spaces):

wget -R mp3,mp4,wav http://example.com/media/

• Using wildcards: The reject flag also accepts wildcard patterns. For instance, if you want to reject files that end with a specific suffix or pattern, you can use asterisks:

wget -R "*back*" http://example.com/downloads/

How it Works with Mirroring

The reject flag is particularly powerful when combining it with the recursive download flag (-r) or the mirroring flag (-m). While wget will still parse the pages to find new links, it will automatically discard and refuse to save any file to your hard drive that matches the blacklisted extensions in your -R command.