Open Chrome or Edge on your Mac and drag the .mbox onto readmbox.com to read it without importing anything. If it's an Apple Mail export, it's a folder: drag the file called mbox from inside it.
When you use Mailbox → Export Mailbox… in Apple Mail, you get something like Inbox.mbox. It looks like a file but it's a folder, and the mail is in a plain file named mbox inside it, next to a small table_of_contents file.
Inbox.mbox in Finder. If Finder opens it in Mail instead, right-click and choose Show Package Contents.mbox onto the viewer. Drag-and-drop works even though the file has no extension.Google Takeout and Thunderbird exports are ordinary single files, so you can drag them straight in.
| Method | How | Good for |
|---|---|---|
| This viewer | Drag the file onto readmbox.com in Chrome or Edge | Reading, searching and exporting without importing. Huge files. |
| Apple Mail | File → Import Mailboxes…, choose Files in mbox format, then pick the file | Adding the mail to Apple Mail permanently |
| Thunderbird | Copy the file into the Local Folders directory, then restart | A free email program that also runs on Windows and Linux |
Apple Mail's import copies everything into Mail's own storage, and very large Takeout files can take a long time and a lot of disk space. If you only need to look something up, reading it in place is quicker.
~/Library/Mail/, in a versioned folder. Mail uses its own internal format there, not MBOX, so use Export Mailbox… to get an MBOX.~/Library/Thunderbird/Profiles/<profile>/Mail/Local Folders/. The mailbox files have no extension (for example Inbox), and each one sits next to an .msf index file.To see ~/Library in Finder, hold Option and open the Go menu.
The viewer is built and tested for desktop Chrome and Edge, which both run on macOS. Install one of them if you normally use Safari.
How to Open & Read MBOX Files – 3 Easy Ways (Apple Mail section) on YouTube
Drag it onto readmbox.com in Chrome or Edge to read it without importing, or import it into Apple Mail with File → Import Mailboxes.
Apple Mail exports each mailbox as a folder ending in .mbox. The mail itself is in the file named mbox inside it. Open or drag that file.
Yes. Unzip the Takeout archive and drag All mail Including Spam and Trash.mbox onto the viewer in Chrome or Edge.
Use desktop Chrome or Edge. Both are free for macOS and are the browsers the viewer is built for.
Ready? Your file stays on your computer.
Open your .mbox file