Android - How to delete backups made using Clockworkmod?

Clockworkmod stores its backups in /sdcard/clockworkmod/backup (replace /sdcard with the path for your external card if you're looking for backups to external memory). With versions prior to 6.0, you can move off (or delete) the entire directory to clear space. The entire backup is self-contained.

If you're using a 6.0 or greater version of Clockworkmod, this is no longer the case. The information about the backup is still in /sdcard/clockworkmod/backup, but the actual data is now stored in /sdcard/clockworkmod/blobs and is deduplicated between backups. The upside is that this should save some space between multiple backups. The downside is you can't just move off or delete a backup directory. With 6.0+, you now have to delete that folder, and then run the "free space" option. Initiating a new backup will automatically free space.

If you are using a version newer than 6.0 I'd recommend you use the delete backup function in CWM.

It's in backup and restore -> delete (and delete from external SD). Doing this will ensure that you don't delete a blob that is being used in another backup, as all backups now share the same blob directory.

After deleting from either place use the function recover free space from that same menú to delete the unused blobs