Internet Calendaring and Scheduling Core Object Specification (iCalendar)
RFC 5545

• Status
• IESG evaluation record
• IESG writeups
• Email expansions
• History

• Versions
• 10

Network Working Group                               B. Desruisseaux, Ed.
Request for Comments: 5545                                        Oracle
Obsoletes: 2445                                           September 2009
Category: Standards Track

     Internet Calendaring and Scheduling Core Object Specification
                              (iCalendar)

Abstract

This document defines the iCalendar data format for representing and
exchanging calendaring and scheduling information such as events,
to-dos, journal entries, and free/busy information, independent of any
particular calendar service or protocol.

Status of This Memo

   This document specifies an Internet standards track protocol for the
   Internet community, and requests discussion and suggestions for
   improvements.  Please refer to the current edition of the "Internet
   Official Protocol Standards" (STD 1) for the standardization state
   and status of this protocol.  Distribution of this memo is unlimited.

Copyright and License Notice

   Copyright (c) 2009 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the BSD License.

   This document may contain material from IETF Documents or IETF
   Contributions published or made publicly available before November
   10, 2008.  The person(s) controlling the copyright in some of this
   material may not have granted the IETF Trust the right to allow
   modifications of such material outside the IETF Standards Process.
   Without obtaining an adequate license from the person(s) controlling
   the copyright in such materials, this document may not be modified
   outside the IETF Standards Process, and derivative works of it may
   not be created outside the IETF Standards Process, except to format

Desruisseaux                Standards Track                     [Page 1]
RFC 5545                       iCalendar                  September 2009

   it for publication as an RFC or to translate it into languages other
   than English.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   5
   2.  Basic Grammar and Conventions . . . . . . . . . . . . . . . .   6
     2.1.  Formatting Conventions  . . . . . . . . . . . . . . . . .   6
     2.2.  Related Memos . . . . . . . . . . . . . . . . . . . . . .   7
   3.  iCalendar Object Specification  . . . . . . . . . . . . . . .   8
     3.1.  Content Lines . . . . . . . . . . . . . . . . . . . . . .   8
       3.1.1.  List and Field Separators . . . . . . . . . . . . . .  11
       3.1.2.  Multiple Values . . . . . . . . . . . . . . . . . . .  11
       3.1.3.  Binary Content  . . . . . . . . . . . . . . . . . . .  11
       3.1.4.  Character Set . . . . . . . . . . . . . . . . . . . .  12
     3.2.  Property Parameters . . . . . . . . . . . . . . . . . . .  12
       3.2.1.  Alternate Text Representation . . . . . . . . . . . .  13
       3.2.2.  Common Name . . . . . . . . . . . . . . . . . . . . .  15
       3.2.3.  Calendar User Type  . . . . . . . . . . . . . . . . .  15
       3.2.4.  Delegators  . . . . . . . . . . . . . . . . . . . . .  16
       3.2.5.  Delegatees  . . . . . . . . . . . . . . . . . . . . .  16
       3.2.6.  Directory Entry Reference . . . . . . . . . . . . . .  17
       3.2.7.  Inline Encoding . . . . . . . . . . . . . . . . . . .  17
       3.2.8.  Format Type . . . . . . . . . . . . . . . . . . . . .  18
       3.2.9.  Free/Busy Time Type . . . . . . . . . . . . . . . . .  19
       3.2.10. Language  . . . . . . . . . . . . . . . . . . . . . .  20
       3.2.11. Group or List Membership  . . . . . . . . . . . . . .  20
       3.2.12. Participation Status  . . . . . . . . . . . . . . . .  21
       3.2.13. Recurrence Identifier Range . . . . . . . . . . . . .  22
       3.2.14. Alarm Trigger Relationship  . . . . . . . . . . . . .  23
       3.2.15. Relationship Type . . . . . . . . . . . . . . . . . .  24
       3.2.16. Participation Role  . . . . . . . . . . . . . . . . .  25
       3.2.17. RSVP Expectation  . . . . . . . . . . . . . . . . . .  25
       3.2.18. Sent By . . . . . . . . . . . . . . . . . . . . . . .  26
       3.2.19. Time Zone Identifier  . . . . . . . . . . . . . . . .  26
       3.2.20. Value Data Types  . . . . . . . . . . . . . . . . . .  28
     3.3.  Property Value Data Types . . . . . . . . . . . . . . . .  29
       3.3.1.  Binary  . . . . . . . . . . . . . . . . . . . . . . .  29
       3.3.2.  Boolean . . . . . . . . . . . . . . . . . . . . . . .  30