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| layout: default |
| title: ICU Documentation |
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| description: ICU Documentation |
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| <!-- |
| © 2020 and later: Unicode, Inc. and others. |
| License & terms of use: http://www.unicode.org/copyright.html |
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| # ICU Documentation |
| |
| [](https://icu.unicode.org/) |
| |
| ## ICU User Guide |
| |
| The [ICU User Guide](./userguide) provides information on i18n topics for which ICU has services, and |
| includes details that go beyond the C, C++, and Java API docs (and avoids some duplication between them). |
| |
| This is the new home of the User Guide (since 2020 August). |
| |
| ## ICU Site |
| |
| The official ICU Site is located at https://icu.unicode.org/. |
| It is the official landing page for the ICU project. |
| |
| Some of the pages from the ICU Site have been migrated here. |
| The migrated sections and pages from the ICU Site are visible in the navigation bar of this site below the "ICU Site" section heading. |
| |
| ## Downloading ICU |
| |
| The [Downloading ICU](download) page has been migrated here. |
| |
| ### Latest Release |
| |
| ***2025-10-30: [ICU 78](78.md) is now available*** — |
| [releases/tag/release-78.1](https://github.com/unicode-org/icu/releases/tag/release-78.1) — |
| Maven: [com.ibm.icu / icu4j / version 78.1](https://mvnrepository.com/artifact/com.ibm.icu/icu4j/78.1) |
| |
| ICU 78 updates to |
| [Unicode 17](https://www.unicode.org/versions/Unicode17.0.0/) |
| ([blog](https://blog.unicode.org/2025/09/unicode-170-release-announcement.html)), |
| including new characters and scripts, emoji, collation & IDNA changes, and corresponding APIs and implementations. |
| |
| It also updates to |
| [CLDR 48](https://cldr.unicode.org/downloads/cldr-48) |
| ([blog](https://blog.unicode.org/2025/10/unicode-cldr-48-available.html)) |
| locale data with new locales, and various additions and corrections. |
| |
| In Java, there is a new Segmenter API which is easier and safer to use than BreakIterator.\ |
| In C++, there is a new set of APIs for Unicode string (UTF-8/16/32) code point iteration |
| that works seamlessly with modern C++ iterators and ranges. |
| |
| The Java implementation of the |
| [CLDR MessageFormat 2.0 specification](https://www.unicode.org/reports/tr35/tr35-messageFormat.html) |
| has been updated to CLDR 48. |
| The core API has been upgraded to “draft”, while the Data Model API remains in technology preview. |
| |
| The C++ implementation of MessageFormat 2.0 is at CLDR 47 level and remains in technology preview. |
| |
| ICU 78 and CLDR 48 are major releases, including a new version of Unicode and major locale data improvements. |
| |
| ## ICU team member pages |
| |
| Other documentation pages here are written by and for team members. |
