mboxgrep is a small utility that scans a mailbox for messages matching a regular expression. Found messages can be either displayed on standard output, counted, deleted, piped to a shell command or written to another mailbox.


  • support for mbox (either plain or compressed), MH, nnmh, nnml and maildir folders
  • ability of reading mbox folders and out from another mboxgrep process from standard input
  • support for basic and extended POSIX regular expressions, and optionally, Perl-compatible regular expressions (if linked with the PCRE library)
  • ability of limiting the search to message body or headers (although the whole message is scanned by default)
  • message counting
  • recursive search through directories
  • ability to invert the sense of matching
  • ability to write found messages to another mailbox
  • filtering duplicate messages


  • current unstable version is 0.7.11
  • current stable version is not yet available