A country code top-level domain (ccTLD) is an

Internet The Internet (or internet) is the global system of interconnected computer networks that uses the Internet protocol suite (TCP/IP) to communicate between networks and devices. It is a ''internetworking, network of networks'' that consists ...

top-level domain generally used or reserved for a

country A country is a distinct part of the world, such as a state, nation, or other political entity. It may be a sovereign state or make up one part of a larger state. For example, the country of Japan is an independent, sovereign state, whil ...

, sovereign state, or dependent territory identified with a country code. All

ASCII ASCII ( ), abbreviated from American Standard Code for Information Interchange, is a character encoding standard for electronic communication. ASCII codes represent text in computers, telecommunications equipment, and other devices. Because ...

ccTLD identifiers are two letters long, and all two-letter top-level domains are ccTLDs. In 2018, the Internet Assigned Numbers Authority (IANA) began implementing internationalized country code top-level domains, consisting of language-native characters when displayed in an end-user application. Creation and delegation of ccTLDs is described in RFC 1591, corresponding to ISO 3166-1 alpha-2 country codes. While gTLDs have to obey international regulations, ccTLDs are subjected to requirements that are determined by each country’s domain name regulation corporation. With over 150 million domain name registrations today or as of 2022, ccTLDs make up about 40% of the total domain name industry. Country code extension applications began in 1985. The registered country code extensions in that year included

.us .us is the Internet country code top-level domain (ccTLD) for the United States. It was established in early 1985. Registrants of .us domains must be U.S. citizens, residents, or organizations, or a foreign entity with a presence in the United ...

(United States),

.uk .uk is the Internet country code top-level domain (ccTLD) for the United Kingdom. It was first registered in July 1985, seven months after the original generic top-level domains such as .com and the first country code after .us. , it is the fift ...

(United Kingdom) and

.il .il is the Internet country code top-level domain (ccTLD) of Israel, administered by the Israel Internet Association and managed bNIC - ISRAEL which hosts the DNS root server and manages the Israeli Internet Exchange, that supports IPv4 and I ...

(Israel). The registered country code extensions in 1986 included

.au .au is the Internet country code top-level domain (ccTLD) for Australia. It was created on 5 March 1986. Domain name policy is managed by .au Domain Administration (auDA). As of July 2018, the registry is operated by Afilias. History The d ...

(Australia),

.de .de is the country code top-level domain (ccTLD) for the Federal Republic of Germany. DENIC (the Network Information Centre responsible for .de domains) does not require specific second-level domains, and there are no official ccSLDs under .d ...

(Germany), .fi (Finland),

.fr .fr is the Internet country code top-level domain (ccTLD) in the Domain Name System of the Internet for France. It is administered by AFNIC. The domain includes all individuals and organizations registered at the Association française pour le ...

(France),

.is .is (dot is) is the top-level domain for Iceland. The country code is derived from the first two letters of '' Ísland'', which is the Icelandic word for Iceland. Registration of .is domains is open to all people and companies without any specia ...

(Iceland),

.jp The web address suffix .jp is the Internet country code top-level domain (ccTLD) for Japan. It was established in 1986 and is administered by the Japan Registry Services. History At the establishment of the .jp domain, the domain was administe ...

(Japan),

.kr .kr is the Internet country code top-level domain (ccTLD) for the Republic of Korea (South Korea). Registrations are processed via registration agents. From September 2006, it became possible to register domain names directly under .kr (altho ...

(South Korea),

.nl .nl is the Internet country code top-level domain (ccTLD) for the Netherlands. It is one of the most popular ccTLDs with over six million registered .nl domains . When cwi.nl was registered by Centrum Wiskunde & Informatica on 1986-05-01, .nl ...

(Netherlands) and

.se .se, formerly branded as .SE, is the Internet country code top-level domain ( ccTLD) for Sweden Sweden, formally the Kingdom of Sweden,The United Nations Group of Experts on Geographical Names states that the country's formal name is ...

(Sweden). The registered country code extensions in 1987 included

.nz .nz is the Internet country code top-level domain ( ccTLD) for New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five ...

(New Zealand),

.ch .ch is the country code top-level domain (ccTLD) for Switzerland in the Domain Name System of the Internet. Made available in 1987, only two years after .com, it is administered by SWITCH Information Technology Services. The domain ''ch'', as ...

(Switzerland) and

.ca .ca is the Internet country code top-level domain (ccTLD) for Canada. The domain name registry that operates it is the Canadian Internet Registration Authority (CIRA). Registrants can register domains at the second level (e.g., ''example.ca'') ...

(Canada). The registered country code extensions in 1988 included

.ie .ie is the country code top-level domain (ccTLD) which corresponds with the ISO 3166-1 alpha-2 code for Ireland. The Internet Assigned Numbers Authority (IANA) list the Computing Services Computer Centre of University College Dublin as its spo ...

(Ireland)

.it .it is the national top-level domain (ccTLD) assigned to Italy. Registration is open to organisations and individuals of legal age who are citizens or residents of/headquartered in the countries of the European Economic Area (EEA), the Vatica ...

(Italy),

.es .es (espana) is the country code top-level domain (ccTLD) for Spain. It is administered by the Network Information Centre of Spain. Registrations are permitted at the second level or at the third level beneath various generic second level categ ...

(Spain) and

.pt .pt is the Internet country code top-level domain (ccTLD) for Portugal and is managed by Associação DNS.PT. It has the following second-level domains: * .com.pt: no restrictions; online registration * .edu.pt: education * .gov.pt: Governmen ...

(Portugal). In the 1990s,

.cn .cn is the country code top-level domain (ccTLD) for the People's Republic of China introduced on 28 November 1990. Domain name administration in mainland China is managed through a branch of the Ministry of Industry and Information. The registr ...

(People’s Republic of China) and

.ru .ru is the Latin alphabet Internet country code top-level domain ( ccTLD) for Russia introduced on 7 April 1994. The Russian alphabet internationalized country code is .рф. Control of .ru is assigned to the Coordination Center for TLD ...

(Russian Federation) were first registered. There are 308 delegated ccTLDs. The

.tk .tk is the Internet country code top-level domain (ccTLD) for Tokelau, a territory of New Zealand in the South Pacific. It can be registered on the company Freenom. Overview Tokelau allows any individual to register domain names. Users and smal ...

and

ccTLDs contain the highest number of domains. The

.pl is the Internet country code top-level domain (ccTLD) for Poland, administered by NASK, the Polish research and development organization. It is one of the founding members of CENTR. History The domain was created in 1990, following the mit ...

.gr .gr is the country code top-level domain (ccTLD) for Greece. Registrations are processed via accredited registrars and domain names in Greek characters may also be registered. Second level domains There are five official second level domains: ...

.cz .cz is the country code top-level domain (ccTLD) for the Czech Republic. It is administered by CZ.NIC. Registrations must be ordered via accredited domain name registrars. Until Czechoslovakia was dissolved in 1993, it used the domain '' .cs''. ...

.hu .hu is the Internet country code top-level domain (ccTLD) for Hungary Hungary ( hu, Magyarország ) is a landlocked country in Central Europe. Spanning of the Carpathian Basin, it is bordered by Slovakia to the north, Ukraine to the ...

and

ccTLDs do not contain as many domains as other ccTLDs. The top ten ccTLDs account for more than five-eighths of registered ccTLD domains. There were about 153 million ccTLD domains registered at the end of March 2022.

Delegation and management

IANA is responsible for determining an appropriate trustee for each ccTLD. Administration and control are then delegated to that trustee, which is responsible for the policies and operation of the domain. The current delegation can be determined from IANA's list of ccTLDs. Individual ccTLDs may have varying requirements and fees for registering

subdomains In the Domain Name System (DNS) hierarchy, a subdomain is a domain that is a part of another (main) domain. For example, if a domain offered an online store as part of their website example.com, it might use the subdomain shop.example.com . O ...

. There may be a local-presence requirement (for instance, citizenship or other connection to the ccTLD), as, for example, the American ( us), Japanese ( jp),

Canadian Canadians (french: Canadiens) are people identified with the country of Canada. This connection may be residential, legal, historical or cultural. For most Canadians, many (or all) of these connections exist and are collectively the source of ...

( ca),

French French (french: français(e), link=no) may refer to: * Something of, from, or related to France ** French language, which originated in France, and its various dialects and accents ** French people, a nation and ethnic group identified with Franc ...

( fr) and German ( de) domains, or registration may be open.

History

The first registered ccTLD was

, which was registered in 1985. Later ccTLDs registered in that year included

and

. Then,

, .fi,

and

were also registered in 1986. In 1987,

and

were registered. Later on, in 1988,

and

were also registered.

Lists

As of 20 May 2017, there were 255 country-code top-level domains, purely in the Latin alphabet, using two-character codes. The number was 316 , with the addition of internationalized domains. The number is 308 .

Latin Character ccTLDs

: ;Table Notes:

Internationalized ccTLDs

; Table notes:

Proposed internationalized ccTLDs

Internationalised domain names have been proposed for Japan and

Libya Libya (; ar, ليبيا, Lībiyā), officially the State of Libya ( ar, دولة ليبيا, Dawlat Lībiyā), is a country in the Maghreb region in North Africa. It is bordered by the Mediterranean Sea to the north, Egypt to the east, Su ...

Relation to ISO 3166-1

Unused ISO 3166-1 codes

Almost all current ISO 3166-1 codes have been assigned and do exist in DNS. However, some of these are effectively unused. In particular, the ccTLDs for the Norwegian dependency

Bouvet Island Bouvet Island ( ; or ''Bouvetøyen'') is an island claimed by Norway, and declared an uninhabited protected nature reserve. It is a subantarctic volcanic island, situated in the South Atlantic Ocean at the southern end of the Mid-Atlantic ...

( bv) and the designation

Svalbard and Jan Mayen Svalbard and Jan Mayen ( no, Svalbard og Jan Mayen, ISO 3166-1 alpha-2: SJ, ISO 3166-1 alpha-3: SJM, ISO 3166-1 numeric: 744) is a statistical designation defined by ISO 3166-1 for a collective grouping of two remote jurisdictions of Norw ...

( sj) do exist in DNS, but no subdomains have been assigned, and it is Norid policy to not assign any at present. Two

territories— bl ( Saint Barthélemy) and mf (

Saint Martin Saint Martin may refer to: People * Saint Martin of Tours (c. 316–397), Bishop of Tours, France * Saint Martin of Braga (c. 520–580), archbishop of Bracara Augusta in Gallaecia (now Braga in Portugal) * Pope Martin I (598–655) * Saint Mart ...

)— await local assignment by France's government. The code eh, although eligible as ccTLD for Western Sahara, has never been assigned and does not exist in

DNS The Domain Name System (DNS) is a hierarchical and distributed naming system for computers, services, and other resources in the Internet or other Internet Protocol (IP) networks. It associates various information with domain names assigned to ...

. Only one subdomain is still registered in gb (ISO 3166-1 for the

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the European mainland, continental mainland. It comprises England, Scotlan ...

), and no new registrations are being accepted for it. Sites in the United Kingdom generally use uk (see below). The former

.um .um was the Internet country code top-level domain for the United States Minor Outlying Islands. It was administered by the United States Minor Outlying Islands Registry. Until late 2006 USMIR was housed at the University of Southern California ...

ccTLD for the U.S. Minor Outlying Islands was removed in April 2008. Under RFC 1591 rules,

is eligible as a ccTLD on request by the relevant governmental agency and local Internet user community.

ASCII ccTLDs not in ISO 3166-1

Several ASCII ccTLDs are in use that are not ISO 3166-1 two-letter codes. Some of these codes were specified in older versions of the ISO list. * uk (

): The ISO 3166-1 code for the United Kingdom is GB. However, the JANET network had already selected uk as a top-level identifier for its pre-existing Name Registration Scheme, and this was incorporated into the DNS root. gb was assigned with the intention of a transition, but this never occurred and the use of uk is now entrenched. * su This obsolete ISO 3166 code for the

Soviet Union The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, ...

was assigned when the Soviet Union still existed; moreover, new su registrations are accepted. * ac ( Ascension Island): This code is a vestige of IANA's decision in 1996 to allow the use of codes reserved in the ISO 3166-1 alpha-2 reserve list for use by the Universal Postal Union. The decision was later reversed, with Ascension Island now the sole outlier. (Three other ccTLDs, gg ( Guernsey), im ( Isle of Man) and je (

Jersey Jersey ( , ; nrf, Jèrri, label=Jèrriais ), officially the Bailiwick of Jersey (french: Bailliage de Jersey, links=no; Jèrriais: ), is an island country and self-governing Crown Dependencies, Crown Dependency near the coast of north-west F ...

) also fell under this category from 1996 until they received corresponding ISO 3166 codes in March 2006.) * eu (

European Union The European Union (EU) is a supranational political and economic union of member states that are located primarily in Europe. The union has a total area of and an estimated total population of about 447million. The EU has often been ...

): On September 25, 2000, ICANN decided to allow the use of any two-letter code in the

ISO 3166-1 ISO 3166-1 (''Codes for the representation of names of countries and their subdivisions – Part 1: Country codes'') is a standard defining codes for the names of countries, dependent territories, and special areas of geographical interest. It ...

reserve list that is reserved for all purposes. Only EU currently meets this criterion. Following a decision by the EU's Council of Telecommunications Ministers in March 2002, progress was slow, but a registry (named EURid) was chosen by the

European Commission The European Commission (EC) is the executive of the European Union (EU). It operates as a cabinet government, with 27 members of the Commission (informally known as "Commissioners") headed by a President. It includes an administrative body ...

, and criteria for allocation set: ICANN approved eu as a ccTLD, and it opened for registration on 7 December 2005 for the holders of prior rights. Since 7 April 2006, registration is open to all in the European Economic Area.

Historical ccTLDs

ccTLDs may be removed if that country ceases to exist. There are three ccTLDs that have been deleted after the corresponding 2-letter code was withdrawn from ISO 3166-1: cs (for

Czechoslovakia , rue, Чеськословеньско, , yi, טשעכאסלאוואקיי, , common_name = Czechoslovakia , life_span = 1918–19391945–1992 , p1 = Austria-Hungary , image_p1 ...

), zr (for

Zaire Zaire (, ), officially the Republic of Zaire (french: République du Zaïre, link=no, ), was a Congolese state from 1971 to 1997 in Central Africa that was previously and is now again known as the Democratic Republic of the Congo. Zaire was, ...

) and tp (for

East Timor East Timor (), also known as Timor-Leste (), officially the Democratic Republic of Timor-Leste, is an island country in Southeast Asia. It comprises the eastern half of the island of Timor, the exclave of Oecusse on the island's north-we ...

). There may be a significant delay between withdrawal from ISO 3166-1 and deletion from the DNS; for example, ZR ceased to be an ISO 3166-1 code in 1997, but the zr ccTLD was not deleted until 2001. Other ccTLDs corresponding to obsolete ISO 3166-1 codes have not yet been deleted. In some cases they may never be deleted due to the amount of disruption this would cause for a heavily used ccTLD. In particular, the Soviet Union's ccTLD su remains in use more than twenty years after SU was removed from ISO 3166-1. The historical country codes dd for the German Democratic Republic and yd for South Yemen were eligible for a ccTLD, but not allocated; see also de and ye. The temporary reassignment of country code cs ( Serbia and Montenegro) until its split into rs and me (

Serbia Serbia (, ; Serbian: , , ), officially the Republic of Serbia (Serbian: , , ), is a landlocked country in Southeastern and Central Europe, situated at the crossroads of the Pannonian Basin and the Balkans. It shares land borders with Hung ...

and

Montenegro ) , image_map = Europe-Montenegro.svg , map_caption = , image_map2 = , capital = Podgorica , coordinates = , largest_city = capital , official_languages = ...

, respectively) led to some controversies about the stability of ISO 3166-1 country codes, resulting in a second edition of ISO 3166-1 in 2007 with a guarantee that retired codes will not be reassigned for at least 50 years, and the replacement of RFC 3066 by RFC 4646 for country codes used in

language tag An IETF BCP 47 language tag is a standardized code or tag that is used to identify human languages in the Internet. The tag structure has been standardized by the Internet Engineering Task Force (IETF) in ''Best Current Practice (BCP) 47''; the su ...

s in 2006. The previous ISO 3166-1 code for

Yugoslavia Yugoslavia (; sh-Latn-Cyrl, separator=" / ", Jugoslavija, Југославија ; sl, Jugoslavija ; mk, Југославија ;; rup, Iugoslavia; hu, Jugoszlávia; rue, label= Pannonian Rusyn, Югославия, translit=Juhoslavij ...

, YU, was removed by ISO on 23 July 2003, but the yu ccTLD remained in operation. Finally, after a two-year transition to Serbian rs and Montenegrin me, the .yu domain was phased out in March 2010. Australia was originally assigned the oz country code, which was later changed to au with the .oz domains moved to .oz.au.

Internationalized ccTLDs

An internationalized country code top-level domain (IDN ccTLD) is a top-level domain with a specially encoded domain name that is displayed in an end user application, such as a

web browser A web browser is application software for accessing websites. When a user requests a web page from a particular website, the browser retrieves its files from a web server and then displays the page on the user's screen. Browsers are used on ...

, in its native language script or a non-alphabetic

writing system A writing system is a method of visually representing verbal communication, based on a script and a set of rules regulating its use. While both writing and speech are useful in conveying messages, writing differs in also being a reliable for ...

, such as

Latin script The Latin script, also known as Roman script, is an alphabetic writing system based on the letters of the classical Latin alphabet, derived from a form of the Greek alphabet which was in use in the ancient Greece, Greek city of Cumae, in southe ...

(.us, .uk and .br),

Indic script The Brahmic scripts, also known as Indic scripts, are a family of abugida writing systems. They are used throughout the Indian subcontinent, Southeast Asia and parts of East Asia. They are descended from the Brahmi script of ancient India ...

(.) and Korean script (.), etc. IDN ccTLDs are an application of the

internationalized domain name An internationalized domain name (IDN) is an Internet domain name that contains at least one label displayed in software applications, in whole or in part, in non-latin script or alphabet, such as Arabic, Bengali, Chinese (Mandarin, simplifie ...

(IDN) system to top-level Internet domains assigned to countries, including the

, or independent geographic regions. ICANN started to accept applications for IDN ccTLDs in November 2009, and installed the first set into the Domain Names System in May 2010. The first set was a group of Arabic names for the countries of Egypt, Saudi Arabia, and the United Arab Emirates. By May 2010, 21 countries had submitted applications to ICANN, representing 11 languages. ICANN requires all potential international TLDs to use at least one letter that does not resemble a Latin letter, or have at least three letters, in an effort to avoid IDN homograph attacks. Nor shall the international domain name look like another domain name, even if they have different alphabets. Between Cyrillic and Greek alphabets, for example, this could happen.

Generic ccTLDs

Generic Country Code Top-Level Domain or gccTLD refers to those TLDs which are technically "non-restricted ccTLDs" but used like traditional generic TLDs ( gTLDs) rather than "country"-targeted ones. Most of the gccTLDs are primarily used as domain hacks:

Unconventional usage

Lenient registration restrictions on certain ccTLDs have resulted in various domain hacks. Domain names such as I.am, tip.it, start.at and go.to form well-known English phrases, whereas others combine the

second-level domain In the Domain Name System (DNS) hierarchy, a second-level domain (SLD or 2LD) is a domain that is directly below a top-level domain (TLD). For example, in , is the second-level domain of the TLD. Second-level domains commonly refer to the organ ...

and ccTLD to form one word or one title, creating domains such as blo.gs of

South Georgia and the South Sandwich Islands ) , anthem = " God Save the King" , song_type = , song = , image_map = South Georgia and the South Sandwich Islands in United Kingdom.svg , map_caption = Location of South Georgia and the South Sandwich Islands in the southern Atlantic Oc ...

( gs), youtu.be of

Belgium Belgium, ; french: Belgique ; german: Belgien officially the Kingdom of Belgium, is a country in Northwestern Europe. The country is bordered by the Netherlands to the north, Germany to the east, Luxembourg to the southeast, France to ...

( be), del.icio.us of the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...

( us), and

cr.yp.to 





Daniel Julius Bernstein (sometimes known as djb; born October 29, 1971) is an American German mathematician, cryptologist, and  computer scientist. He is a visiting professor at CASA at Ruhr University Bochum, as well as a research professor o ...

Tonga Tonga (, ; ), officially the Kingdom of Tonga ( to, Puleʻanga Fakatuʻi ʻo Tonga), is a Polynesian country and archipelago. The country has 171 islands – of which 45 are inhabited. Its total surface area is about , scattered over in ...

( to). The .co domain of Colombia has been cited since 2010 as a potential competitor to generic TLDs for commercial use, because it may be an abbreviation for ''company''. Several ccTLDs allow the creation of emoji domains. Some ccTLDs may also be used for typosquatting. The domain ''cm'' of

Cameroon Cameroon (; french: Cameroun, ff, Kamerun), officially the Republic of Cameroon (french: République du Cameroun, links=no), is a country in west- central Africa. It is bordered by Nigeria to the west and north; Chad to the northeast; th ...

has generated interest due to the possibility that people might miss typing the letter ''o'' for sites in the ''com''.

Commercial use

Some of the world's smallest countries and non-sovereign or colonial entities with their own country codes have opened their TLDs for worldwide commercial use, some of them free like

Notes

References

External links

* * * * * {{DEFAULTSORT:Country Code Top-Level Domain International telecommunications Top-level domains Country codes Domain Name System

Delegation and management

History

Lists

Latin Character ccTLDs

Internationalized ccTLDs

Proposed internationalized ccTLDs

Relation to ISO 3166-1

Unused ISO 3166-1 codes

ASCII ccTLDs not in ISO 3166-1

Historical ccTLDs

Internationalized ccTLDs

Generic ccTLDs

Unconventional usage

Commercial use

See also

Notes

References

External links