Skip to main content

Make Your Systems UA-Ready

Universal Acceptance (UA) allows users to access the Internet in their chosen online identities, including in their local languages and scripts. By becoming UA-ready, private sectors, governments, and civil societies have the ability to better serve their communities and take advantage of significant business opportunities. According to a 2017 study published by the Universal Acceptance Steering Group (UASG), UA-readiness is a $9.8+ billion opportunity.

The UASG and ICANN have multiple resources to help make your own systems and email services UA-ready. If you would like to discuss how to become UA-ready or have questions, please email

UA Test Frameworks and Materials

Are You EAI-Ready?

Supporting Email Address Internationalization (EAI) is part of being UA-ready.

EAI allows the use of non-English (non-ASCII) characters in either the domain name, the mailbox (local part) name, or both. Examples include:

To check if your email server supports EAI, use the tool available at or send an email to one of the email addresses in UASG 004, and look to see if you get an auto-response.

Additional Resources

View a full list of UA resources.

Case Studies

UA case studies provide real world examples of UA adoption.

Role of ccTLDs in Achieving UA-Readiness

A whitepaper that identifies what a country code top-level domain (ccTLD) manager must do internally to make their systems UA-ready, and how ccTLD managers can encourage UA adoption by local stakeholders.

UA Quick Guide (UASG 005)

Definitions of key terms, relevant RFCs, and recommended next steps to become UA-ready.

Introduction to Universal Acceptance (UASG 007)

An overview of UA with requirements (relevant RFCs), best practices, and recommendations. An introduction to advanced topics such as right-to-left scripts, the Bidi algorithm, and Normalization.

Quick Guide to Email Address Internationalization (EAI) (UASG 014)

An introduction to EAI, and items for email software developers and email service providers to consider.

UA Relevant Standards and RFCs (UASG 006)

Standards related to UA to make your systems UA-ready.

Frequently Asked Questions (FAQs): UA-Readiness of Programming Languages and Email Tools (UASG 031)

Answers to questions on UA support in programming languages and frameworks, and on support for EAI in email tools and services.

EAI Technical Education and Awareness Directed at Developer Community Websites – Proposed FAQs (UASG 044A)

Frequently Asked Questions (FAQs) and answers related to: Character/Length, General Validation, Programming Language, and General IDN/EAI Protocol.

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."