Wikipedia:External links

Wikipedia articles may include external links, links to web pages outside Wikipedia. External links normally should not be placed in the body of an article. All external links must conform to certain formatting restrictions.

Some acceptable external links include those that contain further research that is accurate and on-topic, information that could not be added to the article for reasons such as copyright or amount of detail, or other meaningful, relevant content that is not suitable for inclusion in an article for reasons unrelated to its accuracy.

Some external links are welcome (see § What can normally be linked), but it is not Wikipedia's purpose to include a lengthy or comprehensive list of external links related to each topic. No page should be linked from a Wikipedia article unless its inclusion is justifiable according to this guideline and common sense. The burden of providing this justification is on the person who wants to include an external link.

Besides those kinds of links listed in § Restrictions on linking, .

these external-link guidelines do not apply to citations to reliable sources within the body of the article

If the website or page to which you want to link includes information that is not yet a part of the article, consider using it as a source for the article, and citing it. Guidelines for sourcing, which include external links used as citations, are discussed at Wikipedia:Reliable sources and Wikipedia:Citing sources.

For policy or technical reasons, editors are restricted from linking to the following, without exception:

There are several things that should be considered when adding an external link.

Each link should be considered on its merits, using the following guidelines. As the number of external links in an article grows longer, assessment should become stricter. When in doubt about the appropriateness of adding new links, make a suggestion on the article's talkpage and discuss with other editors.

Except for ,[5] one should generally avoid providing external links to:

External link sections are not prohibited at the end of stand-alone lists or at the end of articles that contain embedded lists. However, the lists themselves should not be composed of external links. These lists are primarily intended to provide direct information and internal navigation, not to be a directory of sites on the web.

Lists in Wikipedia articles may take any of multiple forms, including bullet lists (most common), numbered lists, horizontal lists, tables (standard for Wikipedia:Featured lists), etc. The rules about whether to include an external link in a list apply regardless of the method used to format the list.

This section does not apply if the external link is serving as a citation to a reliable source for a stand-alone list entry that otherwise meets that list's inclusion criteria. To determine whether an item should be included in the list at all, refer to . To determine how to format citations to reliable sources, see Wikipedia:Citing sources.

In other cases, such as for lists of political candidates and software, a list may be formatted as a table, and appropriate external links can be displayed compactly within the table:

In some cases, these links may serve as both official links and as inline citations to primary sources. In the case of elections or other one-time events, it may be desirable to replace the original links with links to archived copies when the event is over.

It is obvious that a link from Wikipedia to an external site may drive Web traffic to that site. But in line with Wikipedia policies, you should avoid linking to a site that you own, maintain, or represent—even if Wikipedia guidelines seem to imply that it may otherwise be linked. When in doubt, you may go to the talk page and let another editor decide. This suggestion is in line with Wikipedia's conflict-of-interest guidelines.

Wikipedia uses the same standards for evaluating links to websites owned by for-profit and (real or purported) non-profit organizations. Links to potentially revenue-generating web pages are not prohibited, even though the website owner might earn money through advertisements, sales, or (in the case of non-profit organizations) donations. Choose which pages to link based on the immediate benefit to Wikipedia readers that click on the link, not based on the organization's tax status or your guess at whether the website's owner might earn money from the link.

A few parties now appear to have a spambot capable of spamming wikis from several different wiki engines, analogous to the submitter scripts for guestbooks and blogs. If you see a bot inserting external links, please consider checking the other language wikis to see if the attack is widespread. If it is, please report it on Meta; they can put in a Wikimedia-wide text filter. Administrators will block unauthorized bots on sight.

In biographies of living persons, material available solely in questionable sources or sources of dubious value should be handled with caution, and, if derogatory, should not be used at all, either as sources or via external links. External links in biographies of living persons must be of high quality and are judged by a higher standard than for other articles. Do not link to websites that are not fully compliant with this guideline or that contradict the spirit of WP:BLP.

Outside of citations,[5] external links to websites that require registration or a paid subscription to view should be avoided because they are of limited use to most readers. Facebook and many online newspapers require registration to access some or all of their content, while some require a subscription. Online magazines frequently require subscriptions to access their sites or for premium content. If old newspaper and magazine articles are archived, there may be a fee for accessing them.

A site that requires registration or a subscription should not be linked unless the website itself is the topic of the article (see § Official links) or the link is part of an inline reference (see Wikipedia:Citing sources). Bibliographic citations should normally cite the most authoritative source for the publication (e.g., a copy of the newspaper article on the original newspaper's website rather than a copy on someone's blog), but may add a link to a free version if one is available and not a copyright violation.

Outside of citations,[5] external links to English-language content are strongly preferred in the English-language Wikipedia. It may be appropriate to have a link to a non-English-language site, such as when an official site is unavailable in English; or when the link is to the subject's text in its original language; or when the site contains visual aids such as maps, diagrams, or tables—per the guideline on non-English-language sites.

Note that this guideline does not apply to references, which can be in any language, though English is preferred if available and equally reliable. See Wikipedia:Verifiability#Non-English sources for Wikipedia's standards for published sources that are not written in English. It is preferred that a language icon, or the |lang= parameter of a citation template, also be used to indicate the source language.

URL redirection sites are not to be used. Examples of these sites include tinyurl.com, tiny.cc and the .tk top level domain. Most of these sites are listed in the m:Spam blacklist because they are frequently abused by link spammers, which means that it is not possible to save a page that contains such a link. Because URL redirection sites are added to the blacklist whenever abuse occurs, you may create problems for future editors by using them. Adding links to web proxies is prohibited for a similar reason. Instead, one should add a link to the original URL.

It is generally preferred to link to the exact destination of a link. For instance, if example.com is an automatic redirect to example.org/example, it is better to link to the exact page, even if the webmaster considers the redirect address to be more official.

It is acceptable to link to pages rendered in normal HTML or plain text, but this is not always the case with pages using rich media formats (which may be incompatible with many users' settings and browsers). Check that the content type of the linked page is text/html, text/plain, or application/xhtml+xml (or another XHTML content type) as some pages may instead be rendered solely by platform-dependent plugins. Try to avoid directly linking to any content that requires special software, or an add-on to a browser. It is always preferred to link to a page rendered in normal HTML that contains embedded links to the rich media.

Where a link to rich media is deemed appropriate, either as a direct link or embedded within an HTML page, an explicit indication of the technology needed to access the relevant content must be given, as in the following examples:

Note that MediaWiki software will provide small icons for several types of outgoing links, such as the PDF example above but text that makes it explicit is still helpful for the reader.

While there is no blanket ban on linking to YouTube or other user-submitted video sites, the links must abide by the guidelines on this page. (See § Restrictions on linking and § Links normally to be avoided.) Many videos hosted on YouTube or similar sites do not meet the standards for inclusion in External links sections, and copyright is of particular concern. Many YouTube videos of newscasts, shows, or other content of interest to Wikipedia visitors are copyright violations and should not be linked, either in the article or in citations. Links should be evaluated for inclusion with due care on a case-by-case basis. Links to online videos should also identify additional software necessary for readers to view the content.

On articles with multiple points of view, avoid providing links too great in number or weight to one point of view, or that give undue weight to minority views. Add comments to these links informing the reader of their point of view. If one point of view dominates informed opinion, that should be represented first. For more information, see Wikipedia:Neutral point of view—in particular, Wikipedia's guidelines on undue weight.

Wikidata should not be linked to within the body of an article except in the manner of hidden comment(s) mentioning the Q-number. For further information, see this discussion.

An official link is a link to a website or other Internet service that meets both of the following criteria:

Official links (if any) are provided to give the reader the opportunity to see what the subject says about itself. These links are normally exempt from the links normally to be avoided, but they are not exempt from the restrictions on linking. For example, although links to websites that require readers to register or pay to view content are normally not acceptable in the External links section, such a link may be included when it is an official website for the subject. This exemption does not allow for additional "official" links such as those found on fundraising websites.

No official link exists for many articles. "Fansites", including everything from websites run by fans of a musician to a charitable organization supporting patients with a disease, even if they are endorsed or authorized by the subject, are not considered official websites because the subject of the article cannot control the information being presented. Links to websites that are not considered official websites may still be justifiable under other sections of this guideline, e.g., Links to consider #4.

Web sites sometimes get hijacked or hacked. This is often done to serve malware. If an official site is serving malware, its URL should be hidden until the website is cleaned up. This can usually be accomplished by commenting out the website using the procedure at Help:Hidden text along with a note in the comment explaining that the official site is a malware site. The website could also be inserted by an infobox, in which referring to the infobox's documentation can be useful in finding out how to suppress the automatic link. If you suppress a site's URL, please leave a comment explaining why you did so, using the hidden text feature.

Normally, only one official link is included. If the subject of the article has more than one official website, then more than one link may be appropriate, under a very few limited circumstances.[8] However, Wikipedia . Wikipedia does not attempt to document or provide links to every part of the subject's web presence or provide readers with a handy list of all social networking sites. Complete directories lead to clutter and to placing undue emphasis on what the subject says.

More than one official link should be provided only when the additional links provide the reader with significant unique content and are not prominently linked from other official websites. For example, if the main page of the official website for an author contains a link to the author's blog and Twitter feed, then it is not appropriate to provide links to all three. Instead, provide only the main page of the official website in this situation. In other situations, it may sometimes be appropriate to provide more than one link, such as when a business has one website for the corporate headquarters and another for consumer information. Choose the minimum number of links that provide readers with the maximum amount of information. Links that provide consistent information are strongly preferred to social networking and communication services where the content changes rapidly and may not comply with this guideline at any given moment in time. Wikipedia does not exist to facilitate corporate "communication strategies" or other forms of marketing.

It is very important to consider whether the link is likely to remain relevant and acceptable to the article in the foreseeable future. For example, it is not useful to link to a webpage that changes often and merely happens to have a relevant picture or article on its front page at the moment. Consider locating and linking to permalink versions of web content, and trying to find resources that have a commitment to keeping content available at the same address.

Links to dead URLs in a list of external links are of no use to Wikipedia articles. Such dead links should either be updated or removed. In rare cases, such as the official website for a notable political campaign, it may be better to replace the dead link with a link to an archived copy of the website. Note, however, that the matter is different for references, which link to archived webpages far more often.

It may be worth checking to see if there is a working version of the link in an earlier version of the article. Some dead links are caused by vandalism; for example, a vandal may disable links to products competing with the vandal's favored product. Some instances of this type of vandalism are quite subtle, such as replacing ASCII letters in the URL with identical-looking Cyrillic letters.

URLs can be "hijacked" or re-registered for a different purpose after a (domain name) registration expires.[9] Even if the URL seems to remain valid (it still "works"), if it no longer points to the desired information, then it needs to be handled as a dead link.

All text following a space is taken as the text to use for the link. Embedding wikilinks into the link text is incorrect; instead choose the appropriate words to link.

If there are no meaningful words that can be used for the link, a link with no text is preferred to using self-referential link text, such as "click here" or "this link". These types of self-references should be avoided.

http: or https: should be explicitly specified as appropriate for the target site (preferring https:, where available). The linking style [//www...] without protocol is obsolete and should not be used in external links.

If an article has external links, the standard format is to place them in a bulleted list under a primary heading at the end of the article. External links should identify the link and briefly summarize the website's contents and why the website is relevant to the article. The heading should be "External links" (plural) even when only a single link is listed. If several external links are listed and the subject of the article is a living person, organization, web service, or otherwise has an official website, it is normal practice to place the link to that site at the top of the list.

This External links section is one of the optional standard appendices and footers, which appear in a defined order at the bottom of the article.

If you link to another website, you should give your reader a good summary of the site's contents, and the reasons why this specific website is relevant to the article in question. If you link to an online article, try to provide as much meaningful article information as possible. For example:

Sites that have been used as sources in the creation of an article should be cited in the article and linked as references, either in-line or in a references section. Links to these source sites are not "external links" for the purposes of this guideline, and should not normally be duplicated in an external links section. Exceptions—websites that can be both references and external links—include any official sites for the article topic, or websites that are specifically devoted to the topic, contain multiple subpages, and comply with the criteria for links to be avoided.

When linking to large database-driven sites like the Internet Movie Database, try to use an external link template. If the URL format of the database ever changes, it is sometimes possible to quickly fix all links by rewriting the template.

Inappropriate and duplicative links may be deleted by any editor; if the reason for the deletion is not obvious, please explain on the article's talk page.

Inline templates may be useful for flagging individual links that you want to further discuss on the article's talk page:

If a new or unregistered user persists in adding an inappropriate link to one or more pages, please consider leaving a message for User:XLinkBot. This bot will automatically revert listed sites if added by non-autoconfirmed users, but permit other editors to add them. For malware or serious spamming, please read Wikipedia:Spam blacklist and Wikipedia:WikiProject Spam to recommend site-wide blacklisting.

Two maintenance categories list all tagged articles that need attention to remove spam and non-compliant links. They are:

In April 2014, each of these categories listed about 4,000 articles that had been tagged for assistance with external links and spam. Any editor can address these concerns by applying the advice on this page. When an article complies with the relevant standards, then any editor may remove the tags.

Special:Linksearch is a tool to search for URLs in external links. For example, one might search for all Wikipedia pages linking to yahoo.com at Special:Linksearch/*.yahoo.com.

This guideline describes the most common reasons for including and excluding links. However, the fact that a given link is not actually prohibited by this guideline does not automatically mean that it must or should be linked. Every link provided must be justifiable in the opinion of the editors for an article. Disputes about links can be addressed through the normal dispute-resolution process, particularly at the external links noticeboard.

Disputed links should normally be excluded by default unless and until there is a consensus to include them.