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History of Unicode Release and Publication Dates

For ease of reference, this page collects together information about the dates for various releases of the Unicode Standard, as well as details regarding publication dates for the books and Unicode Technical Reports associated with Unicode releases.

Dates for Each Release of the Unicode Standard

The formal release dates for each version of the Unicode Standard, as documented in Enumerated Versions, have come to be associated with the date when the Unicode Character Database data files for a version have been completed and announced. However, note that for the very earliest versions of the Unicode Standard, there were no data files; the release of data files started with Version 2.0.0.

For major and minor versions, the release dates may differ from the publication dates for the associated documentation. In particular, Unicode Standard Annexes carry their own dates, which mark the last date the document was modified before the Unicode release date for that version. The publication dates for Unicode book publications and the Unicode core specifications typically are later than the Unicode release date for that version, because of the longer time it takes to complete their editing for publication.

Unicode Release Dates

Version Year Month (Day)
8.0.0 2015 June 17
7.0.0 2014 June 16
6.3.0 2013 September 30
6.2.0 2012 September 26
6.1.0 2012 January 31
6.0.0 2010 October 11
5.2.0 2009 October 1
5.1.0 2008 April 4
5.0.0 2006 July 14
4.1.0 2005 March 31
4.0.1 2004 March
4.0.0 2003 April
3.2.0 2002 March
3.1.1 2001 August
3.1.0 2001 March
3.0.1 2000 August
3.0.0 1999 September
2.1.9 1999 April
2.1.8 1998 December
2.1.5 1998 August
2.1.2 1998 May
2.0.0 1996 July
1.1.5 1995 July
1.1.0 1993 June
1.0.1 1992 June
1.0.0 1991 October

Version 1.1.5 was not a release formally approved by the Unicode Technical Committee. However, the very first version of UnicodeData.txt became available in July, 1995. It contained data for the repertoire of Unicode 1.1, and that data file has come to be known as Unicode Version 1.1.5.

Publication Dates for the Unicode Core Specification

Title Year Month (Day)
The Unicode Standard, Version 7.0 2014 October 8
The Unicode Standard, Version 6.2 2012 November 16
The Unicode Standard, Version 6.1 2012 April 23
The Unicode Standard, Version 6.0 2011 February 18
The Unicode Standard, Version 5.2 2009 December 23

A separate core specification for Version 6.3 was never published, in part because it would have been trivially distinct from the core specification for Version 6.2 and in part because of the priority given to the major editorial work required to prepare Version 7.0.

The first five chapters of the core specification for Version 5.2 were published the same day as the data release: October 1, 2009. The remaining chapters were published December 23, 2009.

Publication Dates for the Unicode Standard Books

Title Publication Year First Printing Date CDROM
The Unicode Standard, Version 5.0 2007 October, 2006
The Unicode Standard, Version 4.0 2003 August
The Unicode Standard, Version 3.0 2000 January
The Unicode Standard, Version 2.0 1996 July
The Unicode Standard, Version 1.0, Volume 2 1992 June  
The Unicode Standard, Version 1.0, Volume 1 1991 October  

Note that for various reasons involving the publication production schedule, the publication dates for Version 3.0 and Version 5.0 are the subsequent year after the date associated with the data release for that version.

Version 2.0 had multiple print runs. The third printing was dated July, 1998.

Publication Dates of UTRs for Minor Releases

Title Report Number Date
The Unicode Standard, Version 3.2 UAX #28 March 27, 2002
The Unicode Standard, Version 3.1 UAX #27 May 16, 2001
The Unicode Standard, Version 2.1 UTR #8 September 4, 1998
The Unicode Standard, Version 1.1 UTR #4 1993

UTR #8, the reference documentation for Version 2.1, was originally published on September 4, 1998. However, an updated Revision 3 of UTR #8 was published on November 21, 1999, to correct some formatting problems in the HTML of Revision 2 of the report.

In addition to the published books and UAXes or UTRs documenting released versions of the Unicode Standard, there were a number of identifiable pre-publication drafts of the first version of the Unicode Standard. Some of these drafts were intended for internal review; others were bound and were widely distributed for public review. The following table identifies major milestone drafts and dates for this pre-publication history of the standard.

Dates of Pre-publication Drafts

Title Author Date Distribution
The Unicode Standard, Worldwide Character Encoding, Version 1, Pre-Copy-Edit Draft The Unicode Consortium May 7, 1991 Members
Unicode 1.0, Draft Standard, Final Review Document The Unicode Consortium December, 1990 Public
Unicode 1.0, Han Character Supplement, Draft Standard, Final Review Document The Unicode Consortium December, 1990 Public
Unicode Preview The Unicode Consortium October, 1990 Public
Unicode Working Draft Unicode90 Consortium August, 1990 UWG
Unicode 88 Joseph D. Becker, Ph.D. August 29, 1988  

The Unicode 88 document is the original Unicode manifesto, authored by Joe Becker. It developed the basic principles for the Unicode design and briefly outlined the history and status of the "Unicode Proposal" as of 1988. Some of its content was reworked for inclusion in the early Unicode pre-publication drafts.

The August, 1990 document was a very rough working draft for the standard. The editors and the Unicode Working Group (UWG)―the predecessor of the UTC―used it to help lay out the anticipated content and structure of the standard. It contained no code charts or block descriptions. This draft preceded the final decision about the eventual name of the Unicode Consortium—hence the odd name of the consortium on the title page. The Unicode Consortium was not officially incorporated until January 3, 1991.

The October, 1990 draft was fairly widely distributed. It contained very abbreviated introductory text, initial drafts of the code charts, the first draft of the character names index, the first draft of multi-column Unihan charts, and various mapping tables. It was referred to at the time as "Unicode 0.9".

The December, 1990 drafts were even more widely distributed, including to many international reviewers. They were used to elicit public feedback on the draft standard. They put the participating SC2 national bodies on notice that the Unicode Consortium was serious about developing and publishing its standard. The first volume contained a more extended introduction, a full draft of the non-Han code charts, including the first version of the character names list. It also contained the first drafts of the block descriptions. The second volume contained the multi-column Unihan charts and the draft of the Han block introduction. At the time these draft volumes were referred to collectively as the "Final Review Draft".

The May 7, 1991 draft was complete content, intended for final Unicode Consortium membership review and approval, of the non-Han part of the draft standard prior to copy editing with the eventual publisher, Addison-Wesley.