Download ICU 57

ICU is the premier library for software internationalization, used by a wide array of companies and organizations.

Release Overview

The features for this release include support of CLDR 29 and Unicode 8.0 with grapheme/word/line breaking improved for Emoji sequences.

For more details, including migration issues, see below.

List of tickets fixed in ICU 57

Common Changes

    • CLDR 29: For details of the many changes in CLDR, see CLDR 29.

  • Grapheme/word/line breaking for emoji sequences, based on Unicode 9 proposed rules. See the Unicode emoji break proposal and the Unicode Emoji Technical Report Proposed Update describing the new emoji sequences. (#12081).

  • Four new Unicode emoji properties (#11802).

  • DateFormat day period formatting of "noon", "at night", etc. via new pattern characters b & B, and DateTimePatternGenerator support of C for selecting the customary form (#11872).

    • Except: Formatting of "0:00 midnight" has been disabled because it is confusing except for at the end of an interval.

  • RelativeDateTimeFormatter: Simpler formatting API (#12072).

  • More robust CLDR data loading for MeasureFormat (#11986, #12030), RelativeDateTimeFormatter (#12018), and DateIntervalFormat/DateIntervalInfo (#12013).

  • New simple & fast SimpleFormatter class for a trivial subset of MessageFormat as used in CLDR data, e.g., "{0} {1}" (#10896).

ICU4C Specific Changes

  • C API support for RelativeDateTimeFormatter (#12072).

  • Clang annotations for intended switch case fallthroughs, can now compile with -Wimplicit-fallthrough (#12166).

  • Internal header files can be compiled by themselves, for simpler alternative build scripts (#12141).

ICU4J Specific Changes

    • The minimum execution environment was updated to Java 6 (#12022)

    • Compact currency format like "1,2 Mio. €" via CompactDecimalFormat (#10910).

Known Issues

    • There is an impact on performance and memory impact for the first use of transliterators in a process, likely due to the number of new transforms added in CLDR 29 (#12380).

    • C: ICU4C 57.1 does not build with Visual Studio 2015 when using the included project files. See ticket for workaround. (#11822)

    • C: ICU4C 57.1 does not build under IBM i. This should be remedied in ICU 58. (#12701)

Migration Issues

  • ICU4J classes are compiled against Java SE 6 runtime and the class file format was changed to Java 6. ICU4J 57 no longer supports JRE 5 or older Java runtime.

  • There are details on migration issues that may result from CLDR changes on CLDR 29 Migration.

  • The ICU license file has been reformatted to plain text and renamed (#12037).

Updates in ICU 57.2

    • New Japanese era Reiwa (令和) support

    • IANA tzdata2019a

ICU4C Download

Latest ICU4C 57 Release

Version: 57.2

Release Date: 2019-04-11

Source and binary downloads are available on the git/GitHub tag page:

Previous ICU4C 57 Releases

Version: 57.1

Release Date: 2016-03-23

ICU4J Download

Latest ICU4J 57 Release

Version: 57.2

Release Date: 2019-04-11

Source and binary downloads are available on the git/GitHub tag page:

Maven dependency:






Previous ICU4 Releases

Version: 57.1

Release Date: 2016-03-23