Is an .mbox file a backup of everything in an Inbox (or other mailbox)?

[Dorner2011]

Question is pretty much what's in the subject. I exported my entire inbox from Mail onto an external hard drive to save space. Is every e-mail, attachment, etc. from my inbox now copied onto my external HDD? If not, is there a way to do that (short of Time Machine)?

After giving my computer plenty of time to think, it spat out about 5 .mbox files of anywhere from 800 MB to 2.15 GB apiece. In total, about 7.5 GB. System Information shows the space Mail takes up is 16.2 GB. I don't send a ton of e-mails, so I'm concerned that the .mbox files are not complete, full archives of my inboxes.

Mac OS Mojave, mid-2012 MBP non-retina. Thanks, y'all.

 

[Runs For Fun]

Those should be complete archives. You would have to open and inspect them to confirm but they should contain everything.

 

[Dorner2011]

Thank you! Any way to "inspect" them short of importing them back into Mail?

 

[chown33]

1) I'm not sure the mbox files include attachments. It's possible it does, but it would be best to confirm this.

2) The mbox format is documented, so you could open them in a programming editor and see what they look like. If you're unfamiliar with doing this kind of manual inspection, or you think it'll be too tedious, then importing is a reasonable choice.

3) I strongly recommend using a new local user account to test importing. Create it in System Preferences > Users and Groups. This will isolate anything you do to that account only. You can delete the local account after you're done with it.

4) I also recommend making a test-case mbox out of only a handful of representative emails, and importing that. If you choose typical emails, such as 5 rich text, 5 plain text, 5 with attachments of different kinds and sizes, then you only need to check 15 emails in your new test user account. This should take far less time and work than trying to verify multiple GB of mbox files.