Single-letter second-level domains are domains in which the second-level domain of the domain name consists of only one letter, such as . In 1993, the Internet Assigned Numbers Authority (IANA) explicitly reserved all single-letter and single-digit second-level domains under the top-level domains com, net, and org, and grandfathered those that had already been assigned. In December 2005, ICANN considered auctioning these domain names.
Active single-letter domains On December 1, 1993, the Internet Assigned Numbers Authority (IANA) explicitly reserved the remaining single-letter and single-digit domain names. The few domains that were already assigned were grandfathered in and continued to exist.
ASCII single-character domains The six single-letter domains in existence at that time under .com, .net and .org were the following: Domain name 1993 owner Current owneri.net INet Solutions Ltd Saw.comq.com JG Quality Technology Servicesq.net Privately owned Privately ownedx.com Marcel DePaolis & Dave Weinstein X Corp. (subsidiary of xAI)x.org X Consortium X.Org Foundationz.com HomePage.com GMO Internet, Inc.
The .org TLD was subsequently reopened for single-letter domain registrations. These and selected other gTLD and ccTLD single-letter domain names currently in use, typically as shortcuts and URL shorteners, are listed below.
Domain name Current user Usage 0.email Zero Email 2.am2am design2.htURL shortener3.svURL shortener3.ieThree Ireland7.atMeMaila.co Amazon.com URL shortcut for Amazon, generally used by Amazon in SMS messages for informing purchasers of activity on an ordera.svURL shortenera.org b.etBetting Exchange UKb.mw BMW URL shortcut for BMWb.skBike.sk b.tc BTC Inc c.ai character.ai c.ccBrian CartmellPersonal websitec.imC.IM is a general, mainly English-speaking Mastodon instance.c.orgChange.orgURL shortcut for change.orgd.gsDragonsayenURL shortcut for dragonsayen.com (DraGonSayen)d.tubeDTubeVideo sharing platform with peer-to-peer capabilitiese.foundation /e/ Foundation Main website for /e/ Foundation and related software/services, including the /e/ operating system, an Android-based mobile operating systeme.gg Meta Platforms e.im MailTime URL shortcut for MailTime Email Messengere.ml e.ml .eml (email) file viewere.ripAlone Servicese.srlE-GroupMain websitee.sveMedia FoundationMain websitef.orgFinTech Labsg.cn GoogleGoogle's official URL shortcut to help Chinese users locate Googleg.co Google's official URL shortcutg.glg.ggGlobal Grid Galleryg.networkG.NetworkLondon-based ISPg.orgg.vug.vuURL shortenerh.plusUnstable RealityHomepage for the H+ research project, owned by Alessandro Perillii.atMeMaili.emailRocket DomainsEmail servicek.atk-digital Media GmbH & Co KGAustrian News-portalk.imKim DotcomURL shortcut for x.com/kimdotcom (Dotcom's X profile)k.ttCitynews SpAURL shortcut for Citynewsk.vuFreeDNSl.deLeipziger Versorgungs- und VerkehrsgesellschaftCommunal holding of the city of Leipzig, encompassing energy, mobility and water infrastructurel.inkTop Level Designm.coVolvo CarsVolvo Cars' car sharing service, Mm.me Meta Platforms URL shortcut for Messengerm.page mmm.page URL shortcut for mmm.page website buildern.pr NPR URL shortcut for public radio network NPRn.school The New School Website of The New School in Moscowo.baby URL shortenero.co Overstock.com URL shortcut for Overstock.como.keo.keq.comQTS Data CentersMain websiteq.digital Q.Digital, Inc. r.cxURL/Bitcoin Wallet Shortenerr.nfAn instance of the Lemmy social news aggregator software, previously an instance of Libreddit, a private Reddit frontend.s.co Snap Inc. URL shortcut to Snapchat's download pages.deSparkasseURL shortcut for sparkasse.des.idPT Aidi Digital GlobalURL shorteners.teamSteamQuick friend invites and URL shortcut for Steamt.co X Corp. Official URL shortcut of Twitter (now X)t.ly t.ly URL shortenert.me Telegram URL shortcut for Telegramu.ae United Arab Emirates The United Arab Emirates' Government portalu.to u.to URL shortenerv.gd v.gd URL shortenerv.me Visa Inc. URL shortcut for Visav.org V Foundation w.org WordPress Foundation Redirects to wordpress.org, has some assets for wordpress.org (under s.w.org)w.wikiWikimedia FoundationThe official Wikimedia Foundation URL shortenerx.aixAIHomepage URLx.comX (formerly Twitter)x.companyX DevelopmentMain websitex.svSparkVaultCryptography platformx.teamX DevelopmentShortcut to careers pagey.gy URL shortener and QR code servicey.org YMCA of the United States Shortcut to YMCAz.aiZ.aiAI chatbot and coding modelz.pnURL shorteners.eeURL shortenerb.lsURL shortenerg.lsURL shortenerj.lsURL shortenerq.ggURL shortenerq.lsURL shorteneru.lsURL shortenerw.lsURL shortenerz.lsURL shorteneru.nuURL shortener0.sbURL shortener0.tlURL shortener2.peURL shortener2.sbURL shortener3.sbURL shortener4.sbURL shortener5.stURL shortener6.vuURL shortener7.lsURL shortener8.nfURL shortener9.msURL shortenerd.tlURL shortenere.gdURL shortenerf.tlURL shortenerh.foURL shorteneri.vgURL shortenerj.gtURL shortenerl.gtURL shortenerl.nfURL shortenerl.tdURL shortenerm.boURL shortenern.msURL shortenerp.sbURL shortenerq.cgURL shortenerr.glURL shorteners.sbURL shorteners.ttURL shorteneru.nfURL shortenerz.nuURL shortenera.acURL shortenera.ttURL shortenerb.eeURL shortenerb.luURL shortenerc.skURL shortenerd.acURL shortenerf.biURL shortenerh.luURL shortenerh.skURL shortenerk.skURL shortenerl.ttURL shortenern.eeURL shortenern.luURL shortenerq.luURL shortenert.eeURL shortenert.luURL shortenert.scURL shorteneru.scURL shorteneru.skURL shortenerv.scURL shortenerx.shURL shortenerz.eeURL shortenerz.shURL shortenerw.pageInitiative site and URL shortenerz.campZcampz.cgURL shortenerz.lightingZumtobel GroupMain website
Many other single-letter second-level domains have been registered under country code top-level domains. The list of country code top-level domains which have been identified to allow single-letter domains are:
.ac .af .ag .ai .am .at .bo .by .bz .cg .cm .cn .co .cr .cx .cz .de .dk .et .fm .fr .gd .gg .gl .gp .gs .gt .gy .hn .hr .ht .ieOne and Two Letter .IE Domains Now Available "The release of short .ie domain names " Dublin, 12 October 2015 .im .io .isISNIC Icelandic Domain Rules, Retrieved on 22 September 2021. .je .kg .ki .kw .la .lb .lc .lu .ly .md .mg .mk .mp .ms .mw .mx .mu .nf .np .nz .pe .ph .pk .pl .pn .pr .pw .ro .sc .sh .sk .st .tc .tl .tt .to .tv .ua .uk .vc .vg .vn .vuVerisign The World's Shortest Domain Names: How To Get a One Character Domain, Copenhagen, 01 December 2014. Retrieved on 04 December 2014. .ws
Non-ASCII single-character domains Single-character non-ASCII second-level domains also exist (as seen below), also known as Internationalized domain names (IDN), these domains are actually registered as their Punycode translations (which are more than a single character) for DNS purposes. ICANN oversees a process for determining registration rules that involves wide-ranging stakeholder input and assorted Working Groups. In the case of .com domains, decisions are then implemented by Verisign, the contracted backend operator for the .com registry. The result is a list of 96,957 codepoints allowed for IDN registrations.Verisign Registration Rules: Allowed Code Points, Reston VA, 01 July 2011. Retrieved on 06 April 2019. As mentioned above, some additional domains previously registered are "grandfathered" and remain active. Many gTLDs also allow IDN registration.
These 96,957 distinct IDN characters eligible for registration in .com are the essential building-blocks of languages worldwide. A single letter domain does not provide the context found in a longer string or group of words. They may appear similar to one another or to other English / Latin characters; due to this potential for confusion, browsers have restricted the characters that may be rendered and will display the restricted characters in their Punycode form. They are sometimes used as pictorial symbols and memorable links.
Among IDNs currency symbols are considered extremely rare given their day to day use on mobile keyboards. These domains are grandfathered and if the registration is allowed to lapse, domain will be reserved by the registry. +Currency Symbol Domains Internationalized Domain Name (IDN) Punycode Domain + TLD Usage Registration Date / Registrar (WHOIS entry)¢.com xn--8a.comCrypto website25 April 2004 / Namecheap£.comxn--9a.comCurrency Symbol .COMs25 April 2004 / Namecheap€.comxn--lzg.comCurrency Symbol .COMs5 September 2003 / Domain.com¥.comxn--cba.comCurrency Symbol .COMs5 September 2003 / OnlineNIC, Inc.₩.comxn--izg.comCurrency Symbol .COMs29 August 2004 / Dynadot.com₦.comxn--fzg.comCurrency Symbol .COMs19 June 2004 / Name.com₣.comxn--czg.comCurrency Symbol .COMs19 April 2001 / CSC Corporate Domains, Inc.฿.comXN--T4C.COMCurrency Symbol .COMs03 September 2009 / Name.com₮.comxn--nzg.comCurrency Symbol .COMs11 September 2005 / Name.com₯.comxn--ozg.comCurrency Symbol .COMs11 September 2005 / Name.com₱.comxn--qzg.comCurrency Symbol .COMs18 June 2004 / DomainSite, Inc.₪.comxn--jzg.comCurrency Symbol .COMs19 April 2001 / CSC Corporate Domains, Inc.₰.comxn--pzg.comCurrency Symbol .COMs04 October 2005 / Name.com