Using Dropbox as an online backup only

Question

Note that this isn't the primary function of Dropbox. As you know, the Dropbox site and apps are for syncing files to users and your other devices.
 
However, there is a way using a workaround to keep your files only on the Dropbox site, to keep them safe online, and yet not take up space on your devices.

Jay · Answer

So now, any time you want to ‘back something up online and off-site’, drag it into the _BACKUP folder on the computer. This can even include entire folders!

Login to Dropbox.com, open that folder and select the files/folders

Move them to the new folder you created.

Once the move is complete, those files will ‘disappear’ from your computer, but they’ll be visible online.

Just like any other selectively ‘unsynced’ folder, you can always opt to make it sync to your computer by checking it from the desktop settings.

Or, if you need specific files, just drag or move them via the site into the _BACKUP folder, wait for it to download automatically, and your files are back on the computer for recovering data you wanted (i.e. to reinstall those 10 Steam games for instance).

This can be done with any account, and can be used even if you use Dropbox to sync as normal, keeping one folder ‘online-only’ in order for a backup to be kept safe. Make sure to uncheck it from the selective sync window on all other devices!

Hopefully this should help for all you archivists out there!

Jay · Answer

Let's prep your account for this:

Create two folders in your Dropbox folder, it doesn’t matter matter what you call them. For the sake of simplicity, I called them ‘_BACKUP’ and ‘BACKUP’

Via Selective Sync in the desktop app ‘Sync’ tab, uncheck the BACKUP folder so it no longer appears on your computer. Keep _BACKUP ticked.

You should have this in the Dropbox folder on your computer now.

Now we’ve setup the ‘backup’ system. Essentially, you use the _BACKUP folder as a temporary go-between to the offline folder, moving files physically off your computer but kept in the cloud.

Jay · Answer

First, a brief recap on the Dropbox features. Smart Sync is a way to view all your files on your computer, while only having them take up a fraction of the space.
 
However, as that only comes with Dropbox Plus, Professional and Business plans, you might not have access to this feature.
 
Selective Sync is another way to keep files online, but the entire folder is hidden from your computer, so you can’t simply make your files offline.

Nevertheless, using Selective Sync does give you an indirect method to make Dropbox an online-only storage site. 
 
As this feature is available to all users, I thought it’d be helpful to give this idea to others.