MBOX File Extension

What is an MBOX File Format?

MBOX is one of the most popular file formats, supported by file formats like Apple Mail and Mozilla Thunderbird. An MBOX file stores emails in an organized format as plain text in a single file. It saves messages in a concatenated format. It means one message after the other. The saved email is starting with the 'From' header. Earlier, it was used by Unix host. Later it has become a flexible file format with multiple support.

Learn More about MBOX

Version 1.x of Apple Mail supports MBOX. The file format saves MBOX files in the /User/Library/Mail/Mailboxes/ directory. The upgraded versions of Apple Mail like 2.0 support the .EMLX format that saves messages separately to provide easy search.

The email client, named Opera Mail, was also using MBOX format.

The file format which is similar to MBOX is the MH Message Handling System.

The modified versions of MBOX format are -

• MBOXO is supported by Eudora
• MBOXRD is supported by the Mozilla family email clients including Mozilla, Thunderbird and Netscape