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Internationalized Domain Name (IDN) Service

Please note that the English language version of all translated content and documents are the official versions and that translations in other languages are for informational purposes only.

The Internationalized Domain Name (IDN) Service gives registry operators the ability to add, modify, or remove the different languages and scripts that they may offer in generic top-level domains (gTLDs) by submitting a service request to ICANN org. The IDN Service process utilizes standard pre-approved Registry Agreement (RA) amendment language and helps streamline processing.

General instructions on how to submit an IDN Service request are provided below. To support the efficiency in ICANN org's review of IDN Service requests, registry operators are encouraged to incorporate solutions provided in the Reference Label Generation Rules (LGR) into the submitted IDN tables, as these LGRs have been reviewed for security and stability. In addition, ICANN has developed an IDN Table Review Tool, that allows registry operators to easily compare their IDN tables with the relevant reference LGRs.

Additional information regarding IDN Service requests is available here. Questions about the process can be addressed by opening a General Inquiry case in the Naming Services portal or by emailing

Add, Modify, or Remove IDN Service(s)

Registry operators may offer Internationalized Domain Names (IDNs) provided the IDN service is reflected in Exhibit A of its Registry Agreement (RA). ICANN org has created an IDN Service request process for gTLD registry operators to add, modify, or remove an IDN service (e.g., languages and scripts offered) to or from its RA. The steps below follow the Registry Service Evaluation Policy (RSEP) and highlight the process used to initiate an IDN Service request.

STEP ONE: Submit an "IDN Service - Add, Modify, or Remove" Request in the Naming Services portal

Follow the steps to (a) confirm the type of request, (b) provide any relevant IDN tables and supporting details, (c) clarify any potential security, stability, or competition concerns and whether current registrations will be impacted with the change in IDN service, and (d) provide signatory information (contact with authority to execute an amendment to the RA).


ICANN reviews the request to ensure the submitted information is complete and reviews the proposed service request to determine if significant security, stability, or competition issues need to be raised with the registry operator.

STEP THREE: Determination and Final Processing

If approved, ICANN org will initiate the authorization process (to execute an RA amendment or issue a free to deploy letter) and ICANN will facilitate the IDN table updates with IANA.

RA Amendment Language Links:

Note: these templates will also be used when adding or removing a language/script.


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"""" is not an IDN."