┌─ FILE ANALYSIS ──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────── ┐
│ DEVELOPER : IETF (Internet Engineering Task Force)
│ CATEGORY : Other
│ MIME TYPE : text/calendar
└ ──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────── ┘
What is an ICS file?
ICS (iCalendar) is the standard file format for calendar data exchange, defined in RFC 5545. ICS files contain event information including dates, times, locations, descriptions, and attendees. They are universally supported by calendar applications and are the backbone of calendar sharing and meeting invitations.
How to open ICS files
- Google Calendar (Web) — Import or subscribe
- Apple Calendar (macOS, iOS) — Double-click to add
- Microsoft Outlook (Windows, macOS) — Import events
- Any text editor — ICS files are plain text
Technical specifications
| Property | Value |
|---|---|
| Standard | RFC 5545 (iCalendar) |
| Encoding | UTF-8 |
| Components | VEVENT, VTODO, VJOURNAL, VFREEBUSY |
| Recurrence | RRULE (RFC 5545 recurrence rules) |
| Time Zones | VTIMEZONE or TZID references |
Common use cases
- Meeting invitations: Email-based calendar invites.
- Calendar subscriptions: Subscribing to shared calendars.
- Event export: Exporting events from calendar apps.
- Scheduling: Booking systems and appointment tools.