Wikipedia.org, WordPress.org and NTP.org lead this list of popular .org websites.

I ranked the 60 public, human-facing sites below with the Tranco list dated 28 August 2026, then checked each homepage on 29 August.

This is a domain popularity ranking, not a league table of the best organisations.

Tranco combines several web, link and DNS signals over 30 days. Its raw results also contain ad systems and technical endpoints, so I removed domains that do not operate as public websites.

You can inspect the method after the table.

The 60 most popular .ORG websites

Rank	Website	Main use
1	Wikipedia.org	Collaborative encyclopaedia
2	WordPress.org	Open-source publishing software
3	NTP.org	Network Time Protocol resources
4	nginx.org	Web server software
5	Mozilla.org	Firefox and open-web work
6	Apache.org	Open-source software foundation
7	Archive.org	Digital library and web archive
8	W3.org	Web standards
9	CreativeCommons.org	Open licences and shared knowledge
10	Telegram.org	Messaging service
11	Wikimedia.org	Wikimedia project portal
12	Debian.org	Linux distribution
13	GNU.org	Free software movement
14	UN.org	United Nations information
15	CookieDatabase.org	Cookie and privacy reference
16	IETF.org	Internet standards development
17	arXiv.org	Research preprints
18	NPR.org	News, radio and podcasts
19	IEEE.org	Engineering association
20	UNESCO.org	Education, science and culture
21	Cambridge.org	Academic publishing
22	ISO.org	International standards
23	OpenStreetMap.org	Collaborative map data
24	Python.org	Python language and community
25	AllAboutCookies.org	Privacy and security guidance
26	HBR.org	Business research and commentary
27	MayoClinic.org	Health information and care
28	FrontiersIn.org	Open-access research publishing
29	WorldBank.org	Development data and projects
30	TheNAI.org	Digital advertising standards
31	Change.org	Petitions and campaigns
32	WEForum.org	World Economic Forum
33	ArchiveOfOurOwn.org	Fanworks archive
34	Ecosia.org	Search engine
35	PBS.org	Public television and education
36	Craigslist.org	Classified advertisements
37	AdblockPlus.org	Ad-blocking software
38	OECD.org	Policy data and analysis
39	Spamhaus.org	Internet threat intelligence
40	APA.org	Psychology association
41	HLTV.org	Counter-Strike coverage
42	LetsEncrypt.org	Free TLS certificates
43	Coursera.org	Online learning
44	JW.org	Religious information
45	Lichess.org	Online chess
46	PLOS.org	Open-science publishing
47	Kernel.org	Linux kernel archives
48	PostgreSQL.org	Database software
49	JSTOR.org	Academic research library
50	Aternos.org	Game-server hosting
51	Wiktionary.org	Collaborative dictionary
52	TGJU.org	Financial market data
53	BBB.org	Consumer and business profiles
54	IANA.org	Internet identifier coordination
55	FedoraProject.org	Fedora Linux project
56	EFF.org	Digital-rights advocacy
57	Syosetu.org	Community fiction publishing
58	ACM.org	Computing association
59	FAO.org	Food and agriculture work
60	ACS.org	Chemistry association

How I ranked the list

I used Tranco list N2Q8W, dated 28 August 2026.

Tranco averages popularity ranks from five providers over the preceding 30 days and combines them with the Dowdall method.

Those sources include browser usage, backlinks and DNS activity, so the result does not equal monthly visitor numbers.

I then applied four editorial checks:

1. The registrable domain had to end in .org.

2. The domain had to serve a public website that a person could use.

3. The homepage had to show a current official-site signal.

4. The domain had to remain on .org rather than redirect to another extension.

That filter removed ad-serving endpoints, CDN domains, DNS utilities and other machine-facing infrastructure. It also removed ampproject.org, which now redirects to amp.dev. I excluded adult sites for publication fit.

Rankings change as the underlying signals change. Treat this as a dated snapshot rather than a permanent order.

The mix shows why .org means more than charity: technology and knowledge sites account for a substantial share of this ranked set.

Ranks 1-10: the web’s most visible .ORG names

1) Wikipedia.org

Wikipedia provides a multilingual, community-edited encyclopaedia. Its memorable domain has become almost inseparable from free public knowledge.

2) WordPress.org

WordPress distributes the open-source WordPress software, themes, plugins and documentation. The .org site represents the community project, while WordPress.com sells a hosted service.

3) NTP.org

NTP publishes Network Time Protocol software and documentation. Computers and networks use NTP to keep their clocks synchronised.

4) nginx.org

[nginx](https://nginx.org/) hosts the open-source nginx web server project. Administrators use the site for downloads, documentation, security notices and release information.

5) Mozilla.org

Mozilla connects Firefox with Mozilla’s broader work for an open, accessible internet. It combines product downloads, policy work and public-interest technology.

6) Apache.org

The Apache Foundation supports a large family of open-source projects. Its site links developers to project pages, governance, licences and community resources.

7) Archive.org

The Internet Archive preserves websites, books, audio, video and software. Its Wayback Machine lets you inspect earlier versions of web pages.

8) W3.org

W3C develops standards and guidance for the World Wide Web. Developers consult the site for specifications, accessibility guidance and working-group activity.

9) CreativeCommons.org

Creative Commons publishes licences and tools that help creators share work on stated terms. The domain supports a global open-knowledge movement rather than a single product.

10) Telegram.org

Telegram uses its .org domain for its messaging apps, features and downloads. It also proves that .org registration does not require charity or nonprofit status.

Ranks 11-20: open projects, standards and institutions

11) Wikimedia.org

Wikimedia acts as a portal to Wikipedia, Wiktionary, Wikidata and related projects. The foundation uses the domain to connect its family of free-knowledge sites.

12) Debian.org

Debian develops a community-run Linux distribution. Visitors find downloads, package information, documentation, security updates and contributor guidance.

13) GNU.org

GNU represents the GNU operating system and free-software movement. The site combines software, philosophy, licences and campaign material.

14) UN.org

The United Nations publishes information on peace, human rights, development and international cooperation. The short domain matches an institution recognised around the world.

15) CookieDatabase.org

Cookie Database helps people identify website cookies, scripts and services. Its privacy-reference role fits the informational expectations many visitors attach to .org.

16) IETF.org

The IETF develops the technical standards that help the internet work. Its site hosts working-group information, meeting material and links to standards documents.

17) arXiv.org

arXiv hosts research papers across physics, mathematics, computer science and other fields. Researchers often share manuscripts there before or alongside journal publication.

18) NPR.org

NPR publishes news, analysis, music, radio programmes and podcasts. Its address reflects the public-media organisation behind the content.

19) IEEE.org

IEEE serves engineers, technologists and researchers through publications, standards, events and professional membership. Its initials make the domain short and easy to remember.

20) UNESCO.org

UNESCO covers education, science, culture and communication. The site connects policy, programmes, data and resources from the UN agency.

Ranks 21-30: research, maps, health and policy

21) Cambridge.org

Cambridge hosts Cambridge University Press & Assessment content, including books, journals, learning resources and exams. The domain shows that major academic publishers also use .org.

22) ISO.org

ISO publishes information about international standards and the organisations that develop them. Businesses use the site to understand standards across quality, safety and technology.

23) OpenStreetMap.org

OpenStreetMap builds an editable map of the world from community contributions. Developers, researchers and public services reuse its open geographic data.

24) Python.org

Python provides the language download, documentation, tutorials, package links and community news. The Python Software Foundation supports the site and wider ecosystem.

25) AllAboutCookies.org

All About Cookies publishes consumer guidance on privacy, security and online tools. The site uses .org for an educational resource even though the extension alone does not prove independence.

26) HBR.org

HBR publishes Harvard Business Review articles, research and management ideas. It is another reminder that publishers and commercial services can legitimately use .org.

27) MayoClinic.org

Mayo Clinic combines health information with details about its clinical services. Its reputation comes from the medical organisation and editorial standards, not from the extension by itself.

28) FrontiersIn.org

Frontiers publishes open-access research journals across science, health and the humanities. Researchers use the site to read, submit and review scholarly work.

29) WorldBank.org

The World Bank publishes development data, research, country information and project records. Its datasets give researchers a widely used source for economic and social indicators.

30) TheNAI.org

The NAI represents digital advertising companies and publishes industry principles, opt-out tools and policy material. The site uses the organisation’s current canonical .org domain.

Ranks 31-40: campaigns, media and public trust

31) Change.org

Change.org lets people create and support online petitions. The platform uses a mission-led identity, although a .org ending does not tell you its corporate structure.

32) WEForum.org

The World Economic Forum publishes research, event coverage and policy discussion on global issues. Its abbreviated domain reflects the organisation’s established name.

33) ArchiveOfOurOwn.org

AO3 hosts fan fiction and other fanworks. A nonprofit organisation and volunteer community operate the archive for its users.

34) Ecosia.org

Ecosia runs a search engine and links its business model to climate action. Its .org address supports that public-purpose positioning while the company still operates commercially.

35) PBS.org

PBS brings together programmes, video, schedules and educational material from the US public-broadcasting network. Its domain closely matches its institutional identity.

36) Craigslist.org

Craigslist operates local classified listings for jobs, housing, services and goods. Its long-standing commercial use makes it one of the clearest exceptions to the idea that .org means nonprofit.

37) AdblockPlus.org

Adblock Plus distributes browser extensions that filter advertising and tracking. The site includes downloads, help material and project information.

38) OECD.org

The OECD publishes policy analysis, statistics and country comparisons. Governments, journalists, students and businesses use its data to compare economies and public policy.

39) Spamhaus.org

Spamhaus supplies threat intelligence used to identify spam and other internet abuse. Its website explains data products, research and security work.

40) APA.org

The APA serves psychologists through research, professional guidance, publications and public education. The initials give the American Psychological Association a compact domain.

Ranks 41-50: security, learning and communities

41) HLTV.org

HLTV covers competitive Counter-Strike with news, match results, rankings and statistics. Its presence shows how gaming media can build a major audience on .org.

42) LetsEncrypt.org

Let’s Encrypt provides free automated TLS certificates. The nonprofit certificate authority helped make HTTPS practical for a much larger part of the web.

43) Coursera.org

Coursera offers courses, certificates and degrees from universities and companies. It uses .org despite operating a commercial education platform.

44) JW.org

JW.org serves as the official website of Jehovah’s Witnesses. It publishes religious material, news and information in many languages.

45) Lichess.org

Lichess provides free online chess, tournaments, puzzles and learning tools. Its open-source code and donation-supported model align naturally with .org expectations.

46) PLOS.org

PLOS publishes open-access scientific journals and advocates for open science. The website explains its journals, policies and research initiatives.

47) Kernel.org

Kernel.org hosts Linux kernel releases and development resources. Developers use it as an authoritative source for kernel files and project information.

48) PostgreSQL.org

PostgreSQL supports the open-source database project with downloads, documentation, community news and events. The project has no need to make a commercial promise in its domain.

49) JSTOR.org

JSTOR gives institutions and individuals access to journals, books, images and primary sources. Its domain has become a familiar research destination.

50) Aternos.org

Aternos provides hosted game servers, especially for Minecraft. The service uses advertising and optional products, another example of open .org eligibility.

Ranks 51-60: dictionaries, governance and associations

51) Wiktionary.org

Wiktionary is a collaborative multilingual dictionary from the Wikimedia community. Its .org identity sits alongside Wikipedia and other free-knowledge projects.

52) TGJU.org

TGJU publishes Iranian and international prices for currencies, gold, metals and markets. It demonstrates the international reach and varied subject matter of .org sites.

53) BBB.org

The BBB publishes business profiles, consumer reviews and complaint information through the Better Business Bureau network. Visitors still need to evaluate the underlying evidence rather than trust the extension alone.

54) IANA.org

IANA coordinates global IP address pools, DNS root-zone information and protocol parameter registries. Its work sits close to the technical foundations of domain names.

55) FedoraProject.org

Fedora develops the Fedora Linux distribution and related editions. The site gives users downloads, documentation and ways to participate.

56) EFF.org

The EFF works on privacy, free expression and civil liberties in technology. Its site combines legal analysis, campaigns, tools and supporter information.

57) Syosetu.org

Syosetu provides a Japanese community publishing platform for web fiction. Its ranking shows that a popular .org site need not target an English-speaking or institutional audience.

58) ACM.org

The ACM serves computing professionals and researchers through publications, conferences, education and membership. Its domain matches a well-known professional association.

59) FAO.org

The FAO leads UN work on food and agriculture. Its site publishes programmes, statistics, guidance and reports for a global audience.

60) ACS.org

The ACS supports the chemistry profession through journals, education, careers, standards and membership. The American Chemical Society rounds out the list as another large professional body.

What these .ORG websites reveal

The list does not fit one organisational mould. It includes nonprofits and public bodies, but it also includes publishers, commercial platforms, technical infrastructure projects and member associations.

Three patterns stand out:

• Public purpose matters more than legal form. Many sites centre knowledge, standards, education, public service or an open community.

• Communities use .org well. Open-source projects, professional bodies and volunteer platforms often need participation more than a sales-first identity.

• The extension cannot prove trust. Anyone can register one, so you still need to check the people, evidence, policies and contact details behind a site.

Public Interest Registry, which operates .org, confirms that the extension is open to anyone. You do not need registered-charity status, UK nonprofit status or US 501(c)(3) status.

Should a UK project choose .ORG, .ORG.UK or .COM?

Choose the extension that tells visitors what kind of relationship to expect.

Extension	Strongest fit	Main signal
.org	International causes, communities, associations and open projects	Mission or shared purpose
.org.uk	UK-focused nonprofit and community organisations	UK organisational identity
.com	Businesses, shops and commercial services	Commercial activity

A UK charity can use .org, and a business can use it too. The practical question is whether visitors will understand your purpose immediately. A local organisation may prefer .org.uk; a project serving several countries may find .org easier to carry across borders.

The extension will not improve Google rankings by itself. Your content, reputation, links, technical quality and usefulness do the real work.

Choose a .ORG name people can repeat

Before registration, test the name in ordinary conversation:

• Can someone spell it after hearing it once?

• Does it avoid unnecessary hyphens and numbers?

• Does it still fit if the project expands?

• Could it infringe an existing trade mark?

• Are matching social handles available?

• Does .org set the right expectation?

Our domain guide explains the parts of a domain, while our naming tips help you narrow a shortlist.

When the name is ready, use our domain search to check the .org version and suitable alternatives.

You can register the domain with us, connect it to hosting, and use our site builder when you are ready to publish.

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