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Second-Level Reference Label Generation Rules

ICANN has developed second-level Internationalized Domain Name tables in machine readable format or Label Generation Rules (LGRs) that registry operators can reference during the Pre-Delegation Testing (PDT) phase of the New gTLD Program and while undergoing the Registry Service Evaluation Process (RSEP). Deviation from these LGRs is possible; see PDT and RSEP documentation for more information.

These LGRs have been developed in accordance with community-reviewed guidelines. They are provided below in XML and HTML formats. Also see the Overview and Summary document for further details about the LGRs.

If you have questions or feedback regarding these Reference Label Generation Rules, please send an email to IDNprogram@icann.org.

Language Date Finalized LGR Documents Additional Information
Belarusian 19 December 2016 HTML
XML
Review (L1, L2, SS).
View public comment materials.
Bosnian (Cyrillic) 10 October 2016 HTML
XML
Review (L1, L2, SS).
View public comment materials.
Bosnian (Latin) 10 October 2016 HTML
XML
Review (L1, L2, SS).
View public comment materials.
Bulgarian 10 October 2016 HTML
XML
Review (L1, L2, SS).
View public comment materials.
Chinese 10 October 2016 HTML
XML
Review (L1, SS).
View public comment materials.
Danish 10 October 2016 HTML
XML
Review (L1, L2, SS).
View public comment materials.
English 10 October 2016 HTML
XML
Review (L1, L2, SS).
View public comment materials.
Finnish 10 October 2016 HTML
XML
Review (L1, L2, SS).
View public comment materials.
French 10 October 2016 HTML
XML
Review (L1, L2, SS).
View public comment materials.
German 10 October 2016 HTML
XML
Review (L1, L2, SS).
View public comment materials.
Hebrew 10 October 2016 HTML
XML
Review (L1, L2, SS).
View public comment materials.
Hungarian 10 October 2016 HTML
XML
Review (L1, L2, SS).
View public comment materials.
Icelandic 10 October 2016 HTML
XML
Review (L1, L2, SS).
View public comment materials.
Italian 10 October 2016 HTML
XML
Review (L1, L2, SS).
View public comment materials.
Japanese 27 January 2017 HTML
XML
Review (L, SS).
View public comment materials.
Korean 10 October 2016 HTML
XML
Review (L1, SS).
View public comment materials.
Latvian 10 October 2016 HTML
XML
Review (L1, L2, SS).
View public comment materials.
Lithuanian 10 October 2016 HTML
XML
Review (L1, L2, SS).
View public comment materials.
Macedonian 10 October 2016 HTML
XML
Review (L1, L2, SS).
View public comment materials.
Montenegrin 10 October 2016 HTML
XML
Review (L1, L2, SS).
View public comment materials.
Norwegian 10 October 2016 HTML
XML
Review (L1, L2, SS).
View public comment materials.
Polish 10 October 2016 HTML
XML
Review (L1, L2, SS).
View public comment materials.
Portuguese 10 October 2016 HTML
XML
Review (L1, L2, SS).
View public comment materials.
Russian 10 October 2016 HTML
XML
Review (L1, L2, SS).
View public comment materials.
Serbian 10 October 2016 HTML
XML
Review (L1, L2 , SS).
View public comment materials.
Spanish 10 October 2016 HTML
XML
Review (L1, L2, SS).
View public comment materials.
Swedish 10 October 2016 HTML
XML
Review (L1, L2, SS).
View public comment materials.
Ukrainian 19 December 2016 HTML
XML
Review (L1, L2, SS).
View public comment materials.
Domain Name System
Internationalized Domain Name ,IDN,"IDNs are domain names that include characters used in the local representation of languages that are not written with the twenty-six letters of the basic Latin alphabet ""a-z"". An IDN can contain Latin letters with diacritical marks, as required by many European languages, or may consist of characters from non-Latin scripts such as Arabic or Chinese. Many languages also use other types of digits than the European ""0-9"". The basic Latin alphabet together with the European-Arabic digits are, for the purpose of domain names, termed ""ASCII characters"" (ASCII = American Standard Code for Information Interchange). These are also included in the broader range of ""Unicode characters"" that provides the basis for IDNs. The ""hostname rule"" requires that all domain names of the type under consideration here are stored in the DNS using only the ASCII characters listed above, with the one further addition of the hyphen ""-"". The Unicode form of an IDN therefore requires special encoding before it is entered into the DNS. The following terminology is used when distinguishing between these forms: A domain name consists of a series of ""labels"" (separated by ""dots""). The ASCII form of an IDN label is termed an ""A-label"". All operations defined in the DNS protocol use A-labels exclusively. The Unicode form, which a user expects to be displayed, is termed a ""U-label"". The difference may be illustrated with the Hindi word for ""test"" — परीका — appearing here as a U-label would (in the Devanagari script). A special form of ""ASCII compatible encoding"" (abbreviated ACE) is applied to this to produce the corresponding A-label: xn--11b5bs1di. A domain name that only includes ASCII letters, digits, and hyphens is termed an ""LDH label"". Although the definitions of A-labels and LDH-labels overlap, a name consisting exclusively of LDH labels, such as""icann.org"" is not an IDN."