mbox
What is a .mbox file?
application/mbox
An MBOX file is a mailbox that stores many email messages concatenated into one plain-text file, each message preceded by a 'From ' separator line. It is the classic Unix mailbox format used by many mail clients for export and archival.
How to use a .mbox file
Use an example MBOX to test mailbox splitting, message boundary detection, thread reconstruction, and import into a mail client or parser.
Download example .mbox files
- MBOX Mailbox (three-message thread)An mbox mailbox concatenating a short three-message email thread with the classic 'From ' separator lines and >From body escaping — for testing mailbox splitting and thread reconstruction.
- MBOX Mailbox — six-message threadA larger mbox mailbox with a six-message back-and-forth thread — for testing mailbox splitting, thread reconstruction, and pagination over more than a couple of messages.
- MBOX — Four Charsets and Both Transfer EncodingsOne mailbox whose four messages each use a different charset and alternate between quoted-printable and base64, with RFC 2047 subjects to match. The file itself is LF-stored while the encoded payloads decode to CRLF text — the split every importer has to handle.
- MBOX — Thread Plus Its Bounce, With mboxrd EscapingThree messages in one mailbox: an original whose body contains both a bare "From " line and an already-escaped ">From " line, the reply that threads to it, and the multipart/report bounce that reply triggered. mboxrd escaping is what makes the round trip lossless.
- Git Format-Patch Series - All Four Messages as One MboxThe same four messages concatenated into a single mbox, which is exactly what `git format-patch --stdout` produces and what `git am` consumes. The From_ separator lines use git's fixed sentinel date, so a splitter cannot rely on the timestamp being real.