Downloading ICU

Official Releases

If you want to use ICU (as opposed to developing it), it is recommended that you download an official packaged version of the ICU source code. These versions are tested more thoroughly than day-to-day development builds of the system, and they are packaged in zip and tar files for convenient download. Here are several recent releases of ICU that are available:

Release ICU4C ICU4J Major Changes
ICU 53
CLDR 25, collation code rewrite, measure formatting for various units, relative date formatter and leniency controls in date format parsing
ICU 52
52.1 52.1 CLDR 24, Unicode 6.3, Plurals for fractional values, Islamic Umm al-Qura calendar, DateFormat parse leniency controls and Lao dictionary based word segmentation.
ICU 51
51.2 51.2 CLDR 23, short weekday names, new time zone format patterns, display context for date format and locale display names
ICU 50 50.1.2 50.1.1 CLDR 22.1, Unicode 6.2, ordinal number support, dictionary-based break iterators for Chinese & Japanese…
ICU 49 49.1.2 49.1 CLDR 21.0.1, Unicode 6.1, simpler ICU4C build without generated platform.h, many small API additions

    Note: We have changed the ICU release version numbering, combining the former first two fields into one, thus the major release sequence is ICU 4.8, ICU 49, ICU 50, …
ICU 4.8 CLDR 2.0, MessageFormat rewrite, collation script reordering
ICU 4.6 4.6.1 CLDR 1.9, Unicode 6.0, UTS #46 support, collation enhancements, alternate number symbols
ICU 4.4 4.4.2 CLDR 1.8, Unicode 5.2, compact resource bundle, Java 5 syntax
ICU 4.2 4.2.1 CLDR 1.7 update, Number system
ICU 4.0 4.0.1 CLDR 1.6 update, Unicode 5.1 update, ICU4J charset
ICU 3.8 3.8.1 3.8.1 CLDR 1.5 update, additional calendars, improved time zone support, improved charset conversion performance.
ICU 3.6 3.6 3.6.1 Unicode 5.0 update, UCA 5.0 update, CLDR 1.4 update, ICU4C charset detection, improved ICU4C break iterator
ICU 3.4 3.4.1 3.4.5 Unicode 4.1 update, CLDR 1.3 update, ICU4J charset detection, ICU4C high performance text access
ICU 3.2 3.2.1 3.2 CLDR 1.2 integration.
These are the previous releases of ICU.
Due to the age of these older releases, it is recommended that you use a newer version of ICU for current development.

For more details on building ICU once you've checked out the code, please see the readme.html in ICU.

Latest Development Milestone

The development milestone release is intended for those who want to get an early look at next ICU major release features. It is not recommended for production use.
  • (Not available at this time)

Other Downloads

The following are some ICU tools that are available in addition to ICU.

Tool Description
ICU4J Time Zone Update Utility This tool provides a simple way to update installed copies of ICU4J with the latest time zone data. Updates are required when the rules for transitioning between standard time and daylight (summer) time change in any part of the world.
RB Manager This resource bundle manager allows you to edit your program resource bundles more easily through a user-friendly interface. It also allows importing and exporting of resources to multiple formats.
XLIFF2ICUConverter This tool allows you to convert XLIFF files to ICU ResourceBundle format.
 ICU4JNI  ICU4JNI provides Java Native Interface bindings to ICU4C collation and conversion routines.