How do I exclude folders, file types, or file sizes?

Backblaze allows you to exclude by folder, file type, or file size. You can access the Exclusions pane by opening the Backblaze system preference (Mac) or control panel (Windows), clicking on Settings, and then choosing Exclusions.

Mac:

These are the default folder exclusions (can not be removed, but additional ones can be added):

/Applications, /Library, /private, /System, /bin, /dev, /etc, /net, /sbin, /usr, /Developer

These are the default file type exclusions (can be removed and additional added):

wab~,vmc,vhd,vo1,vo2,vsv,vud,vmdk,vmsn,vmsd,hdd,vdi,vmwarevm,nvram,vmx,vmem,iso,dmg,sparseimage,sys,cab,exe,msi,dll,dl_,wim,ost,o,qtch,log,ithmb

The default maximum file size is No Limit but can be changed to 5 MB, 10 MB, 50 MB, 100 MB, 150 MB, 200 MB, 500 MB, 1000 MB, 2000 MB, 9000 MB, 25000 MB or No Limit.

To add a Folder Exclusion, click the plus sign under the list of folders, navigate to the folder in question, and choose it. It will be excluded during the next scan.

To add a file type exclusion, type in the file extensions in the field, separated by a comma.

To limit the maximum size file that Backblaze will back up, choose another size in the menu.

Windows:

These are the default folder exclusions (can not be removed, but additional ones can be added. The default ones apply to all drives):
 *:\windows\, *:\i386\, *:\$recycle.bin\, *:\$recycler\, *:\msocache\, *:\program files\, *:\program files (x86)\, *:\users\all users\microsoft\, *:\users\all users\microsoft help\

These are the default file type exclusions (can be removed and additional added):

wab~,vmc,vhd,vo1,vo2,vsv,vud,vmdk,vmsn,vmsd,hdd,vdi,vmwarevm,nvram,vmx,vmem,iso,dmg,sparseimage,sys,cab,exe,msi,dll,dl_,wim,ost,o,qtch,log,ithmb

The default maximum file size is No Limit, but can be changed to 5 MB, 10 MB, 50 MB, 100 MB, 150 MB, 200 MB, 500 MB, 1000 MB, 2000 MB, 9000 MB, 25000 MB or No Limit.

To add a Folder Exclusion, click Add Folder..., navigate to the folder in question, and choose it. It will be excluded during the next scan.

To add a file type exclusion, type in the file extensions in the field, separated by a comma.

To limit the maximum size file that Backblaze will back up, choose another size in the menu.

For more advanced exclusions options, refer to this guide: https://help.backblaze.com/hc/en-us/articles/220973007-Advanced-Topic-Setting-Custom-Exclusions-via-XML