CLDR 28 Release Note


Unicode CLDR 28 provides an update to the key building blocks for software supporting the world's languages. This data is used by all major software systems for their software internationalization and localization, adapting software to the conventions of different languages for such common software tasks. The following summarizes the main improvements in the release.

  • General locale data. Overall, about 5% of the data items in this release are new (see Growth), while about 8% have corrections. Notable changes include a major review of and improvement to Spanish locales for Latin America; the addition of two new “modern-coverage” locales (Belarusian and Irish); and moving certain data from en_GB to en_001 for improved quality and reduced data size in locales that use en_GB conventions.

    • Formatting. There are a number of new units and types of formats, with a major revision to the day period rules—preferred for many languages instead of AM/PM (“10:30 at night”)—with localizations; the addition of compact formatting for currencies (“€10M”, “€10 million”), and the addition of more unit measures, including 7 new general units (duration-century), 21 new per-unit types, 4 new units for measuring personal age (needed for some languages), and new coordinate units for formatting latitude and longitude across languages (“10°N”).

    • Identifiers. The new features extend the ability to specify subregions of countries, validate identifiers, and customize locales, including the addition of subdivisions of countries, such as Scotland and California (localized names are not yet present, except for English); the addition of validity data for currency codes, measurement units, and locale identifier elements (allowing validation of Unicode language and locale identifiers without requiring BCP47 data); the addition of seven -u- extension keys and corresponding types to allow customization of locales (“cf” for specifying standard vs accounting currency formats), and the clarification of the specification of identifiers, especially for validity testing.

The specification and charts have also been updated.

Structural additions and changes

BCP47 changes

    • Disallow unicode_language_subtags with 4 letters, to facilitate distinguishing them from unicode_script_subtags. [#8707]

    • Add the unicode_subdivision_subtag to distinguish regions at a finer level than the ISO 3166-1 codes. [#8423]

    • Add variant for Portuguese Language Orthographic Agreement of 1990.

  • New keys and types for locale id -u- extension:

    • key "cf" for currency format style ("standard" or "account"). [#8052]

    • key "fw" for first day of week for calendar display ("sun", "mon", ... , "fri", "sat").

    • key "hc" for hour cycle (0..11, 1..12, 0..23, 1..24).

    • key "lw" for line break to specify CSS level 3 word-break options ("normal", "breakall", "keep all"). [#8204]

    • key "ms" to specify measurement system (metric, ussystem, uksystem). [#7168]

    • key "sd" to specify region subdivision.

    • key "ss" for sentence break to control use of suppressions data ("none" or "standard"). [#7032]

    • for "nu", added math decimal numbering systems [#7098] and numbering systems new in Unicode 8. [#8881]

Main locale data

  • localeDisplayNames

    • New subdivisions/subdivision elements.

  • numbers:

    • Compact currency formatting (“€10M”, “€10 million”) (<currencyFormatLength type="short">). [#5390]

      • Defined number pattern field "¤¤¤¤¤" to designate narrow currency symbol.

  • dates

      • Withdrew COLON as the pattern character designating the timeSeparator symbol. [#8905]

    • dayPeriods translations:

      • for formatting (“10 in the morning”) and

      • for selection (“arrived yesterday morning”

      • Defined new pattern characters b, B, and C to permit specification of dayPeriods in patterns. [#8862]

    • availableFormats, additional standard date skeletons for MMMM: [#8537]

      • "MMMMd"

      • "yMMMM"

  • units

      • new coordinateUnit/coordinateUnitPattern elements: north, east, south, west, for formatting latitude and longitude across languages (e.g. "10°N").

    • many new <perUnitPattern> items for existing units, such as per area-square-centimeter ({0}/cm²).

    • new units:

      • angle-revolution ({0} rev)

      • consumption-liter-per-100kilometers ({0} L/100km)

      • duration-century (0} c)

      • length-mile-scandinavian ({0} smi)

      • speed-knot ({0} kn)

      • volume-pint-metric ({0} mpt)

      • volume-cup-metric ({0} mc)

      • also duration-*-person for languages such as Chinese, where * is one of year, month, week, day

  • casingItem

    • new forceErr attribute to force error instead of warning for unexpected casing in specific data items. [#8250]

Supplemental data

  • New subdivisionContainment and subgroup, for representing subdivisions of countries/regions.

  • New subdivisionAlias, for (future) deprecation of subdivisions.

  • New idValidity for providing subtag validity data.


  • Certain metadata that was in supplemental data or tooling code has been moved into DTD annotations, providing a more visible and maintainable structure. The tooling has been modified to use this information directly:

    • <!--@VALUE--> to indicate that an attribute is not distinguishing, and is treated like an element value.

    • <!--@METADATA--> to indicate that an attribute is a "comment" on the data, like the draft status.

    • <!--@ORDERED--> to indicate that an element's children are ordered.

    • <!--@DEPRECATED--> to indicate that an attribute or element is deprecated.

    • <!--@DEPRECATED:attribute-value--> to indicate that an attribute value is deprecated.

  • Deprecated several collation elements in favor of syntax in the cr element:

    • import, settings, suppress_contractions, and optimize.

    • Deprecated and removed the <generation> element.

  • See ΔDTD28 for details.

Data additions and changes

Data additions and changes that are more likely to cause migration issues are listed in the Migration section below.

    • General locale data

      • New locales in common/main:

        • Added several English locales for Europe and W Asia. [#8642]

      • New locales in common/seed:

        • cv, Chuvash [#8086]

        • bgn, Western Balochi [#8275]

        • mzn, Mazandarani [#8364]

      • az_Arab (replacing azb), South Azerbaijani [#8437]

      • sdh, Southern Kurdish [#8445]

      • Moved to "modern" coverage level: be Belarusian, gd Irish.

      • Major review of and improvement to Spanish locales for Latin America.

      • Moved some data from en_GB to en_001 for improved quality and reduced data size in locales that use en_GB conventions.

      • Improved consistency in casing across locales, mainly by moving to middle-of-sentence as much as possible; the context transforms data can be used to provide appropriate capitalization for different usage contexts. This change primarily impacted date/time symbols.

      • Many updates to the supplemental <territoryInfo> providing information on language use by region.

    • RBNF (number spellout): Improvements to many rulesets, including fixing mistakes, and in various cases adding support for ordinals, fractions, and/or additional grammatical inflections: Arabic, Burmese, Danish, Finnish, Greek, Hebrew, Italian, Norwegian, Portuguese, Russian, Spanish, Thai, Turkish.

  • Date/time:

  • Plurals

    • Added plural rules for be, gd. [#8809]

  • Collation

    • Updated to UCA 8.0. [#8311]

    • Collation settings have been covered to ICU format. [#8289]

    • Added collation for "bo" (same as for "dz"). [#8506]

    • Make native non-Latin script sort first for additional languages: am, chr, ka, lo, mn, ne. [#8575]

  • Segmentation

    • Updated for Unicode 8. [#8418]

  • Transforms

    • Added IPA transcription for Amharic (am), Kyrgyz (ky), Esperanto (eo) and Interlingua (ia).


The following shows the additional coverage in this release.


The following chart shows the coverage levels for this release.


The version 28 Charts are updated for the new data. There are also some changes in the charts themselves:

  • New Territory Subdivisions charts, showing the new CLDR subdivision data.

    • Improved navigation, with an Index link always going up one level.

    • Improved Delta Data charts, with more types of information.

Specification changes

The following summarizes the main changes in the specification. The specification changes are detailed in LDML Modifications.

  • Identifiers

    • Enhanced the unicode language and locale identifiers, and their components.

    • Added unicode_subdivision_subtag.

  • Structure

      • Described new unicode subdivision items, including unicode_subdivision_subtag, validity data, and containment information. See Section 3.6.5 Subdivision Codes.

      • Described new validity data for assessing the validity of unicode language/locale identifiers without requiring BCP47 data, and checking the validity of other identifiers, such as units. See Section 3.11 Validity Data.

    • Added string ranges for UnicodeSets and other data presentation.

  • For numbers,

    • Described how a format with an explicit + can be derived from the CLDR data.

    • Clarified the use of sequences of ¤ characters.

  • For dates,

    • Clarified the matching process for getting from a skeleton (eg yMMMd) to a localized pattern (eg MMM d, yyyy).

    • Added new day-period symbols b, B, and C to Date Field Symbol Table.

    • Added more examples of lenient parsing, such as “a.m.” vs “AM”.

    • Clarified the ISO 8601 timezone formats.

  • Other

Survey Tool

  • Survey Tool has been modified to allow translators to distinguish between a "vote for inherited" and a "hard" vote for a given item.


The following are particular points that may need attention in updating to this version.

  • DTD

    • Various elements have been deprecated, and may need code or parser changes. In particular, the collation sub-elements import, settings, suppress_contractions, and optimize are deprecated. Use equivalent "ICU" syntax inside <cr> elements instead.

  • Locale identifiers

    • CLDR now disallows unicode_language_subtag values of length 4. None of these have been defined up to now, so it is a matter of updating parsers to be future-proof.

    • Validity data for locale identifier elements moved from supplementalMetadata to separate files, with change in structure and more complete information.

  • Locale display names

      • Name for language "ht" changed from "Haitian" to "Haitian Creole" (or equivalent) in en, de, fr. [#8855]

      • Updated Japanese name for Georgia (affects name for region, language, currency, etc.). [#8451]

  • Numbers:

    • Currency symbols changes in root

        • Currency GEL (Georgian Lari): New LARI SIGN ₾ added as variant.

      • Currency RUB (Russian Ruble): RUBLE SIGN ₽ moved from variant to be the default narrow form.

        • Currency TWD (Taiwan Dollar): Default narrow form changed from NT$ to $.

      • Some other currencies were changed in particular locales, such as: in "az", currency AZN now uses the MANAT SIGN. [#8816]

  • Units

    • Many short "per" forms were added, such as "per kilogram" that should be taken advantage of for better formatting of compound units.

  • Dates/times/calendars/zones:

    • Withdrew COLON as the pattern character designating the timeSeparator symbol; note that currently there is no pattern character for timeSeparator.

    • Timezones Asia/Chongqing, Asia/Harbin, and Asia/Kashgar no longer have localizations.

    • For day periods:

      • The older ids for day periods such as {afternoon, earlyMorning, evening, weeHours...} have been replaced by the new ids {morning1, morning2, afternoon1, afternoon2, evening1, evening2, night1, night2}.

      • Deprecated rule attributes 'at' (except for fixed periods), 'after', and 'to' and non-zero minutes/seconds, to allow for simpler implementations.

      • The major cleanup and addition of day period information caused rule changes for most locales. Few implementations were using the previous data, so we don’t anticipate major migration issues.

  • Miscellaneous

    • Many uses of hyphen between numbers were changed to en-dash, eg 123-456 change to 123–456.

    • Postal Codes

      • The deprecated postal codes have now been removed.

    • Plurals

      • Ordinal rules for Irish and Belarusian have been added.

Known issues

    • Invalid language codes in annotations/es_419.xml, annotations/zh_Hant.xml. [#8970]

    • Incorrect symbol in "en_AU" (using Arabic letters) for currency LBP, Lebanese Pound. [#8971]

    • Kazakh has swapped translations for North and South Korea. [#8977]

    • Spaces are missing in Gregorian-calendar standard long and medium date formats for "en_AU". [#9045]

    • The availableFormats patterns for MMMMd have the wrong order in "ar" for Generic/Islamic calendars and in "he" for Gregorian/Islamic calendars; the availableFormats patterns for yMMMM have the wrong order in "ms" for Gregorian/Generic calendars. [#9075, #9110]

    • In the territory containment information in supplementalData.xml, territory "SS" is incorrectly listed as being contained in Northern Africa (015). The correct location is Eastern Africa (014). [#9068]


    • The Release Note contains a general description of the contents of the release, and any relevant notes about the release.

    • The Data link points to a set of zip files containing the contents of the release (the files are complete in themselves, and do not require files from earlier releases -- for the structure of the zip file, see Repository Organization).

    • The Spec is the version of UTS #35: LDML that corresponds to the release.

    • The Delta document points to a list of all the bug fixes and features in the release, which be used to get the precise corresponding file changes using BugDiffs.

    • The SVN Tag can be used to get the files via Repository Access.

The Unicode Terms of Use apply to CLDR data; in particular, see Exhibit 1.

For web pages with different views of CLDR data, see