MacSonik MBOX Viewer is free utility for macOS users which allows them open, view and read MBOX email files without an email client. It helps in accessing all the mailbox content including messages, attachments, headers and other details of the email and retains the original folder structure. The utility is read only and does not change the MBOX files, so it is safe for use when users wish to view archived or backed-up emails and it does not harm or alter the MBOX files. This is really helpful for those who quickly want to see what is stored in an MBOX file without needing to first import it into Apple Mail or Thunderbird.