This is an explanatory essay about the Wikipedia:Reliable sources guideline.

This page provides additional information about concepts in the page(s) it supplements. This page is not one of Wikipedia's policies or guidelines as it has not been thoroughly vetted by the community.

This page is about using Wikipedia as a citation in another Wikipedia article and not about using Wikipedia in general.

For critiques of Wikipedia's reliability for readers, see Wikipedia:Why Wikipedia is not so great. For information on citing Wikipedia as a source in an academic setting, see Wikipedia:Citing Wikipedia.

This page in a nutshell: Do not use a Wikipedia article as a source for another Wikipedia article.

Wikipedia is not a reliable source for citations elsewhere on Wikipedia. As a user-generated source, it can be edited by anyone at any time, and any information it contains at a particular time could be vandalism, a work in progress, or simply incorrect. Biographies of living persons, subjects that happen to be in the news, and politically or culturally contentious topics are especially vulnerable to these issues. Edits on Wikipedia that are in error may eventually be fixed. However, because Wikipedia is a volunteer-run project, it cannot constantly monitor every contribution. There are many errors that remain unnoticed for hours, days, weeks, months, or even years (see Wikipedia:List of hoaxes on Wikipedia). Additionally, it is possible that some errors may never be fixed. It is also possible for an edit correcting an error to later be reverted. Therefore, Wikipedia should not be considered a definitive source in and of itself. This includes articles, non-article pages, The Signpost, and non-English Wikipedias.

The same applies to Wikipedia's sister projects, such as Wiktionary and Wikimedia Commons, as well as websites that mirror or use it as a source themselves, and printed books or other material derived primarily or entirely from Wikipedia articles; see WP:CIRCULAR for guidance.

Wikipedia pages often cite reliable secondary sources that vet data from primary sources. If the information on another Wikipedia page (which you want to cite as the source) has a primary or secondary source, you should be able to cite that primary or secondary source and eliminate the middleman (or "middle-page" in this case).
Always be careful of what you read: it might not be consistently accurate.
Neither articles on Wikipedia nor websites that mirror Wikipedia can be used as sources, because this is circular sourcing.
An exception to this is when Wikipedia is being discussed in an article, which may cite an article, guideline, discussion, statistic or other content from Wikipedia or a sister project as a primary source to support a statement about Wikipedia (while avoiding undue emphasis on Wikipedia's role or views and inappropriate self-referencing).

Articles are only as good as the editors who have been editing them—their interests, biases, education, and background—and the efforts they have put into a particular topic or article. Since we try to avoid original research, a particular article may only be as good as (a) the available and discovered reliable sources, and (b) the subject may allow. Since the vast majority of editors are anonymous, you have only their editing history and their user pages as benchmarks. Of course, Wikipedia makes no representation as to their truth. Further, Wikipedia is collaborative by nature, and individual articles may be the work of one or many contributors over varying periods. Articles vary in quality and content, widely and unevenly, and also depending on the quality of sources (and their writers, editors, and publishers) that are referenced and/or linked. Circumstances may have changed since the edits were added.

Occasionally, inexperienced editors may unintentionally cite the Wikipedia article about a publication instead of the publication itself; in these cases, fix the citation instead of removing it. Although citing Wikipedia as a source is against policy, content can be copied between articles with proper attribution; see WP:COPYWITHIN for instructions.

Philosophy	Article content Articles must be written All Five Pillars are equally important Avoid vague introductions Be a reliable source Civil POV pushing Cohesion Competence is required Concede lost arguments Dissent is not disloyalty Don't lie Don't search for objections Editing Wikipedia is like visiting a foreign country Editors will sometimes be wrong Eight simple rules for editing our encyclopedia Explanationism External criticism of Wikipedia Here to build an encyclopedia Leave it to the experienced Levels of competence Most ideas are bad Need Neutrality of sources Not editing because of Wikipedia restriction The one question Oversimplification Paradoxes Paraphrasing POV and OR from editors, sources, and fields Process is important Product, process, policy Purpose Reasonability rule Systemic bias There is no seniority Ten Simple Rules for Editing Wikipedia Tendentious editing The role of policies in collaborative anarchy The rules are principles Trifecta Wikipedia in brief Wikipedia is an encyclopedia Wikipedia is a community Wikipedia is not RationalWiki
Article construction	100K featured articles Abandoned stubs Acronym overkill Adding images improves the encyclopedia Advanced article editing Advanced text formatting Akin's Laws of Article Writing Alternatives to the "Expand" template Amnesia test A navbox on every page An unfinished house is a real problem Articles have a half-life Autosizing images Avoid mission statements Be neutral in form Beef up that first revision Blind men and an elephant BOLD, revert, discuss cycle Build content to endure Cherrypicking Chesterton's fence Children's lit, adult new readers, & large-print books Citation overkill Citation underkill Common-style fallacy Concept cloud Creating controversial content Criticisms of society may be consistent with NPOV and reliability Deprecated sources Dictionaries as sources Don't demolish the house while it's still being built Don't get hung up on minor details Don't hope the house will build itself Don't panic Don't "teach the controversy" Editing on mobile devices Editors are not mindreaders Encourage the newcomers Endorsements (commercial) Featured articles may have problems Formatting bilateral relations articles Formatting bilateral relations templates Fruit of the poisonous tree Give an article a chance How to write a featured article Identifying and using independent sources History sources Law sources Primary sources Science sources Style guides Tertiary sources Ignore STRONGNAT for date formats Inaccuracy Introduction to structurism Mine a source Merge Test Minors and persons judged incompetent "Murder of" articles Not every story/event/disaster needs a biography Not everything needs a navbox Not everything needs a template Nothing is in stone Obtain peer review comments Organizing disambiguation pages by subject area Permastub Potential, not just current state Presentism Principle of Some Astonishment The problem with elegant variation Pro and con lists Printability Pruning article revisions Publicists Put a little effort into it Restoring part of a reverted edit Robotic editing Sham consensus Source your plot summaries Specialized-style fallacy Stub Makers Run an edit-a-thon Temporary versions of articles Tertiary-source fallacy There are no shortcuts to neutrality There is no deadline There is a deadline The deadline is now Try not to leave it a stub Understanding Wikipedia's content standards Walled garden What an article should not include Wikipedia is a work in progress Wikipedia is not a reliable source Wikipedia is not being written in an organized fashion The world will not end tomorrow Write the article first Writing better articles
Writing article content	Avoid thread mode Copyediting reception sections Coup Don't throw more litter onto the pile Gender-neutral language Myth vs fiction Proseline Use our own words We shouldn't be able to figure out your opinions Write the article first Writing about women Writing better articles
Removing or deleting content	Adjectives in your recommendations AfD is not a war zone Arguments to avoid in deletion discussions Arguments to avoid in deletion reviews Arguments to avoid in image deletion discussions Arguments to make in deletion discussions Avoid repeated arguments Before commenting in a deletion discussion But there must be sources! Confusing arguments mean nothing Content removal Counting and sorting are not original research Delete or merge Delete the junk Deletion is not cleanup Does deletion help? Don't attack the nominator Don't confuse stub status with non-notability Don't overuse shortcuts to policy and guidelines to win your argument Follow the leader How to save an article proposed for deletion I just don't like it Identifying blatant advertising Identifying test edits Immunity Keep it concise Liar liar pants on fire Nothing Nothing is clear Overzealous deletion Relisting can be abusive Relist bias The Heymann Standard Unopposed AFD discussion Wikipedia is not Whack-A-Mole Why was the page I created deleted? What to do if your article gets tagged for speedy deletion When in doubt, hide it in the woodwork No Encyclopedic Use

Essays on civility

The basics	Accepting other users Apology Contributing to complicated discussions Divisiveness Don't retaliate Edit at your own pace Encouraging the newcomers Enjoy yourself Expect no thanks High-functioning autism and Asperger's editors How to be civil Maintaining a friendly space Negotiation Obsessive–compulsive disorder editors Please say please Relationships with academic editors Thank you Too long; didn't read Truce Unblock perspectives We are all Wikipedians here You have a right to remain silent
Philosophy	A weak personal attack is still wrong Advice for hotheads An uncivil environment is a poor environment Be the glue Beware of the tigers! Civility warnings Deletion as revenge Failure Forgive and forget It's not the end of the world Nobody cares Most people who disagree with you on content are not vandals Old-fashioned Wikipedian values Profanity, civility, and discussions Revert notification opt-out Shadowless Fists of Death! Staying cool when the editing gets hot The grey zone The last word There is no Divine Right of Editors Most ideas are bad Nothing is clear Reader The rules of polite discourse There is no common sense Two wrongs don't make a right Wikipedia clichés Wikipedia is not about winning Wikipedia should not be a monopoly Writing for the opponent
Dos	Assume good faith Assume the assumption of good faith Assume no clue Avoid personal remarks Avoid the word "vandal" Be excellent to one another Beyond civility Call a spade a spade Candor Deny recognition Desist Discussing cruft Drop the stick and back slowly away from the horse carcass Encourage full discussions Get over it How to lose Imagine others complexly Just drop it Keep it concise Keep it down to earth Mind your own business Say "MOBY" Mutual withdrawal Read before commenting Settle the process first
Don'ts	ALPHABETTISPAGHETTI Civil POV pushing Cyberbullying Don't accuse someone of a personal attack for accusing of a personal attack Don't be a fanatic Don't be a jerk Don't be an ostrich Don't be ashamed Don't be a WikiBigot Don't be high-maintenance Don't be inconsiderate Don't be obnoxious Don't be prejudiced Don't be rude Don't be the Fun Police Don't bludgeon the process Don't call a spade a spade Don't call people by their real name Don't call the kettle black Don't call things cruft Don't come down like a ton of bricks Don't cry COI Don't demand that editors solve the problems they identify Don't drink the consensus Kool-Aid Don't eat the troll's food Don't fight fire with fire Don't give a fuck Don't help too much Don't ignore community consensus Don't knit beside the guillotine Don't make a smarmy valediction part of your signature Don't remind others of past misdeeds Don't shout Don't spite your face Don't take the bait Don't template the regulars Don't throw your toys out of the pram Do not insult the vandals Griefing Nationalist editing No angry mastodons just madmen No Nazis No racists No Confederates No, you can't have a pony Passive aggression Please don't bite the newcomers POV railroad Superhatting There are no oracles There's no need to guess someone's preferred pronouns You can't squeeze blood from a turnip UPPERCASE
WikiRelations	WikiBullying WikiCrime WikiHarassment WikiHate WikiLawyering WikiLove WikiPeace

Essays on notability

Humorous essays

About essays

About essays	Essay guide Value of essays Difference between policies, guidelines and essays Don't cite essays as if they were policy Avoid writing redundant essays Finding an essay Quote your own essay
Policies and guidelines	About policies and guidelines Policies Guidelines How to contribute to Wikipedia guidance Policy writing is hard

See also