Message and calendar file formats
Formats for personal information: email messages, mailboxes, calendar events and contact cards. The open standards are plain text with named fields, so mail, calendar and address book programs can swap them. Some mail programs also have formats of their own, such as Outlook’s message and data files.
Formats
.EML
Email messageOne email as sent: header fields, then a body with MIME parts.
.EMLX
Apple Mail messageOne Apple Mail message: a byte count, the email, then a property list.
.ICS
iCalendarCalendar events, to-dos and time zones as text content lines.
.MBOX
MailboxA mail folder in one text file, each message after a From line.
.MSG
Outlook messageOne Outlook item, its properties stored as streams in a compound file.
.PST
Outlook data fileA whole Outlook mailbox: folders, mail, calendar and contacts.
.VCF
vCard contactContact cards: names, numbers and addresses as text lines.
.VCS
vCalendarThe calendar format before iCalendar, used by older phones and Outlook.