View source for Wikipedia:Splitting

{{Infopage|WP:SPLIT|WP:SPLITTING|WP:SPLITOUT}} 
{{nutshell|'''Splitting''' is the procedure by which the contents of a page are split into several pages.|The two reasons for splitting are page size and content relevance. For uncontroversial splits, no permission is needed to split; just do it. If unsure, use one of the tags/templates below, and start a discussion on the talkpage.|Use a good edit summary to comply with the [[Wikipedia:Copying within Wikipedia|license requirements]].}}
{{main|Wikipedia:Copying within Wikipedia}}
{{about|splitting of articles|splitting and merging of categories|Wikipedia:Category intersection|splitting of page histories|Wikipedia:History splitting}}

If an article becomes too large, or a section of an article has a length that is out of proportion to the rest of the article, it may be appropriate for some or all of the article to be '''split''' into new articles. In some cases, refactoring an article into child or sister articles can allow subtopics to be discussed more fully elsewhere without dominating a [[WP:General overview article|general overview article]] to which they are non-central (but only if the new articles are themselves sufficiently [[WP:N|notable]] to be included in the encyclopedia).

==When to split==
{{shortcut|WP:WHENSPLIT}}

The two main reasons for splitting material out from an article are size and content relevance. If either the whole article, or the specific material within one section becomes too large, or if the material is seen to be inappropriate for the article due to being [[Wikipedia:Out of scope|out of scope]], then a split may be considered or proposed. '''Consideration must be given to size, notability and potential [[WP:POVFORK|neutrality issues]] before proposing or carrying out a split.'''

===Size split===
{{shortcut|WP:SIZESPLIT}}
{{Main|Wikipedia:Article size}}

Articles should be neither too big nor too small.

Large articles may have readability and technical issues. A page of about 30 to 50&nbsp;[[Byte|kilobytes]] (kB) of readable prose, which roughly corresponds to 6,000 to 10,000 words, takes between 30 and 40 minutes to read at [[reading speed|average speed]], which is right on the limit of the average [[Attention span|concentration span]] of 40 to 50&nbsp;minutes. Also, some users may have technical limitations, such as a low speed service, an unstable connection, or a pay per megabyte service.

At 50&nbsp;kB of readable prose and above it may benefit the reader to consider moving some sections to new articles and replace them with summaries per [[Wikipedia:Summary style]]. Consideration, however, needs to be given to the amount and quality of material to be moved. If the material for the new article is [[Wikipedia:Stub|too short to provide encyclopedic coverage]] of the subject, or would simply duplicate the summary that would be left behind, then it may be too soon to move it. Unsourced material shouldn't be used to create new articles as it may have notability or verifiability issues.

Below 50&nbsp;kB, an article may not need splitting based on size alone, and at 40&nbsp;kB and below a split would generally only be justified based on [[#Content split|content issues]].

{| class="wikitable"
|+ Rule of thumb
|-
! Readable prose size (kB) !! What to do
|-
| style="text-align:center;"| &gt;&nbsp;100 || Almost certainly should be divided
|-
| style="text-align:center;"| &gt;&nbsp;60 || Probably should be divided (although the scope of a topic can sometimes justify the added reading time)
|-
| style="text-align:center;"| &gt;&nbsp;50 || May need to be divided (likelihood goes up with size)
|-
| style="text-align:center;"| &lt;&nbsp;40 || Length alone does not justify division
|-
| style="text-align:center;"| &lt;&nbsp;1 || If an article or list has remained this size for over a couple of months, consider combining it with a related page. Alternatively, why not fix it by adding more info? See [[Wikipedia:Stub]].
|}
Number of characters in an article can be found with the help of [https://xtools.wmflabs.org/articleinfo XTools] (also accessible via Page History from Page Statistics link at the top) under "Prose" in the "General statistics" section; [[User:Shubinator/DYKcheck|Shubinator's DYK tool]]; or [[User:Dr pda/prosesize|Prosesize]].

These guidelines apply somewhat less to [[Wikipedia:Disambiguation|disambiguation]] pages and naturally do not apply to [[Wikipedia:Redirect|redirects]]. They also apply less strongly to [[Wikipedia:List guideline|list]] articles, especially if splitting them would require breaking up a [[Help:Sorting|sortable]] table.

'''Too large after templates are expanded''':
{{main|Help:Template#Template limits}}
{{hatnote|Pages exceeding this limit are in [[:Category:Pages where post-expand include size is exceeded]]}}
After all [[WP:Template|templates]] and [[WP:Transclusion|transclusions]] are accounted for, if the resulting "post-expanded include size" may reach a limit.  Symptoms include templates lower in the page, such as {{tl|reflist}} or [[Wikipedia:Navigation template|navigation templates]] at the bottom of the page not displaying properly. One solution is to split the article.

Since "un-doing" a split may be labor-intensive if significant editing happens to either page after the split, try to avoid splitting until after a community discussion.  If there is another way to reduce the "post-expanded size" that is easier to "undo" than a split, consider doing it first, then opening a discussion to see what the long-term fix should be.

Likewise, if a split would be controversial, try to find a less controversial way to temporarily reduce the "post-expanded size" then open a discussion to find consensus for a long-term fix.

However, if splitting the page is the easiest-to-undo solution and such a split would not be controversial, consider [[WP:BOLD|being bold]] and splitting the page, then immediately opening a discussion to see if the community accepts the split or if it offers alternative solutions.  In this case, be prepared to undo the split.

===Content split===
{{shortcut|WP:CONSPLIT|WP:CONTENTSPLIT}}

Sometimes two or more distinct topics may share the same base title or similar titles, such as "light", which may refer to [[Light|electromagnetic radiation]], [[Lamp (electrical component)|a component that produces light]], or [[Light (theology)|spiritual illumination]]. Sometimes the distinct topics may be closely related, such as ''[[Coffea]]'' (the plant) and [[coffee]] (the product), or [[thermal energy]] and [[heat]].

When two or more distinct topics with the same or a similar titles are being written about on the same page, even if they are closely related, a content split may be considered, and a [[Wikipedia:Disambiguation|disambiguation page]] created to point readers to the separate pages. Before proposing a split, consideration must be given both to [[Wikipedia:Notability|notability]] of the offshoot topic and to potential [[WP:POVFORK|neutrality issues]]. If one or more of the topics is not notable on its own, it may be more appropriate to simply remove the material from Wikipedia than to create a new article.

If unsure, then use a [[#Templates|template]], and start a discussion on the article talkpage.

==Procedure==
{{shortcut|WP:PROSPLIT}}

'''Note:''' For disambiguation pages, use {{tl|Split dab}} instead of {{tl|split}}. If section to be split out is known, use {{tl|split section}}.

'''If an article meets the criteria for splitting and no discussion is required, editors can [[WP:Be bold|be bold]] and carry out the split.''' If unsure, or with high-profile or sensitive articles, start a "Split" discussion on the article talk page, and consider informing any associated WikiProject(s). Additionally, adding one of the [[Wikipedia:Template messages/Splitting| splitting templates]] will display a notice on the article and list it at [[:Category:Articles to be split]]. This will help bring it to the attention of editors who may assist in establishing consensus, in deciding if a split is appropriate, or in carrying out the split. Templates used without an accompanying rationale, and where there is no obvious reason for the split request, may be removed at any time. 

'''Note:''' ''To conform with [[WP:Copyrights|Wikipedia's licensing requirements]], which require that all content contributors receive attribution, the page receiving the split material must have an [[Help:Edit summary|edit summary]] noting "split content from <nowiki>[[article name]]</nowiki>". ('''Do not omit this step or omit the page name'''.) A note should also be made in the edit summary of the source article, "split content to <nowiki>[[article name]]</nowiki>". The {{tl|Copied}} template can also be placed on the talk page of both articles. For further information, refer to the main [[WP:Copying within Wikipedia|Copying within Wikipedia]] guideline.''

==={{anchor|1}}Step 1: Create a discussion===
''Skip to [[#5|step 5]] if making a '''bold''' split.''
Create a discussion on the talkpage of the page that content is to be split from. Include what sections are to be split and what the new page name should be. Example:

<syntaxhighlight lang="moin">
== Splitting proposal ==

I propose that sections ''[[sections]]'' be split into a separate page called ''[[new page name]]''. The content of the current page seems off-topic and these sections are large enough to make their own page. [[User:Tachyony|Tachyony]] ([[User talk:Tachyony|talk]]) 13:30, 9 December 2021 (GMT)
</syntaxhighlight>

''Notify involved users (optional):'' To generate a discussion and to notify people who know a lot about the topic, it is recommended to contact involved users. These users can be: frequent contributors, the creator of the page or users who have a lot of posts on the talk page. You can notify them by <code><nowiki>{{ping |''USER1''|''USER2''|...}}</nowiki></code> or by using a notice for their talk page <code><nowiki>{{Subst:Splitnote | ''ARTICLE NAME'' | ''NEW ARTICLE'' | ''TALK PAGE''}}</nowiki></code>.

[[WP:NOCONSENSUS|Failure to reach a consensus]], whether the result of a split discussion or a bold split that was contested, usually results in the article remaining whole. A contested bold split may be reverted; however it is not always appropriate to redirect the new article to the old as the new article may stand on its own, even if the main article that it came from is not split.

==={{anchor|2}}Step 2: Add notice===
Use {{tlx|split}} to notify users of the proposed split. On the article (not the talkpage) add <code><nowiki>{{split|'''Article 1'''|date=</nowiki>{{#time:F Y}}}}</code> or  <code><nowiki>{{split|'''Article 1'''|'''Article 2'''|...|date=</nowiki>{{#time:F Y}}}}</code>. This template adds a box to notify users about the split. If the new page name is unknown, use <code><nowiki>{{split}}</nowiki></code> by itself with no parameters.

==={{anchor|3}}Step 3: Discuss===
In many cases, a hybrid discussion/straw poll is used, but remember that [[Wikipedia:Polling is not a substitute for discussion|''polling'' is not a substitute for ''discussion'']]. Example formatting:

<syntaxhighlight lang="moin">
 * '''Support''' – <insert reason for supporting split here> [[User:Tachyony|Tachyony]] ([[User talk:Tachyony|talk]]) 13:30, 9 December 2021 (GMT)
 * '''Oppose''' – <insert reason for opposing split here> [[User:Tachyony|Tachyony]] ([[User talk:Tachyony|talk]]) 13:30, 9 December 2021 (GMT)
</syntaxhighlight>

==={{anchor|4}}Step 4: Close the discussion and determine the consensus=== 
Close the discussion and determine the consensus by using the following:
<syntaxhighlight lang="moin">
== Split proposal ==

{{Discussion top|result=The result of this discussion was to ... [[User:Tachyony|Tachyony]] ([[User talk:Tachyony|talk]]) 13:30, 9 December 2021 (GMT)}}

<Start of discussion>
.
.
.
<End of discussion>

{{Discussion bottom}}
</syntaxhighlight>

==={{anchor|5}}Step 5: Perform the splitting===
[[#WP:PROPERSPLIT|See below]].  This is the most important step!

==={{anchor|6}}Step 6: Clean up===
If material is split from an article, consider whether a [[Wikipedia:Summary style|summary section]] should be created, and whether a {{tl|Main}} template should be placed at the top of the section to link to the new page. In general, if the split is due to [[WP:SIZESPLIT|size]], then a summary section is required; if the split is due to [[WP:CONSPLIT|content]] (or [[WP:Out of scope|scope]]), then a summary section is unlikely to be required. On the talk page of the new and old articles, include the template {{tl|Copied}}.

==How to properly split an article==
{{shortcut|WP:CORRECTSPLIT|WP:PROPERSPLIT}}
{{See|Wikipedia:Copying within Wikipedia}}
{{See|Wikipedia:How to fix cut-and-paste moves}}
[[File:Creeks Giving - Climbing in Indian Creek, Utah - 23.jpg|alt=A woman is rock climbing.  She hangs in a difficult spot.|thumb|300px|Don't give up yet!  Splitting an article isn't as difficult as it looks.  There are a lot of steps, but they're pretty easy.  Just take them one at a time until you get to the end of the list.]]

The following procedure can be used for splitting from a single source article to a new article. These instructions are provided for guidance, but some steps may not be necessary in all cases and these instructions may not cover every eventuality. It is advisable to read through the whole of this procedure before starting.

# If the material you want for the new article is scattered around the source article, then prepare the source article by grouping the material to be split out into a single section.  Save your changes with an edit summary like "preparing to split article".  If the material you want for the new article is already in a single section, then skip this step.
# Create the new article by opening the empty page (or redirect page).
# Open the source article (or relevant section) to edit in another browser window (or tab) and copy the contents to be split out (from the section created in step #1) from the source article.
# Paste into the new article with [[Wikipedia:Edit summary|edit summary]] "Contents <nowiki>[[WP:SPLIT]]</nowiki> from <nowiki>[[</nowiki>''Source article name''<nowiki>]]; please see its history for attribution.</nowiki>" and save the new article. 
# Tidy up the new article:
#* The lead sentence will need to be changed to use bold font and usually includes a link to the source article.  
#* A References section should be added and categories should be added. There may also be sections of a bibliography, navboxes, See also section or External links that can be copied from the source article.  
#* Adjust section headings.
#* Add any background information about the parent subject that will be necessary for the reader to understand the subtopic.
#* Resolve any cite errors that occur when invocations of a named reference are separated from their definition{{snd}}i.e. copy the relevant information from the source article.
# Create a good summary of the subtopic at the parent article.
#* Add "<nowiki>{{</nowiki>[[:Template:Main|Main]]|''new article name''<nowiki>}}</nowiki>" (use the order: image, main tag, text). If all the content of the section is being removed (e.g. in the case of a list) use the "[[:Template:See|See]]" template instead of the "Main" template.  If necessary (where there is an image, but only a short paragraph of text) add "<nowiki>{{</nowiki>[[:Template:Clear|Clear]]<nowiki>}}</nowiki>" to the end.  Use the edit summary "Material <nowiki>[[WP:SPLIT]] to [[</nowiki>''New article name''<nowiki>]]</nowiki>" and save the edit.
#* Add a summary, usually of a couple of paragraphs and one image, of the newly created subtopic (unless complete removal is appropriate).
#* There may be some external links, bibliography items, etc. that can be removed from the source article as they are now in the new article.
# Check [[Special:WhatLinksHere]] to see whether some inlinks to the source article (especially any that were to the section that has been split off) can now be changed to point to the new article.
# (Optionally) Add templates referring to the split to the talk pages:
#*If the new article is not being created from scratch (e.g. there is already a redirect) then go to the new article, click on 'View history' tab, select the edit where the copy was made, open it and copy the [[WP:DIFF|diff URL]] of the edit where the cut was made from the browser URL window.
#*If the new article is being created from scratch it's a bit more complicated to obtain a [[WP:DIFF|diff URL]]{{snd}}see [[:Template:Copied]].
#*Open the source article talk page to edit in a new tab.
#*Add template <nowiki>{{Copied|from=|from_oldid=|to=|to_diff=}}</nowiki> to source article talk page, and paste the diff URL into it, add the title of the new article and the date, add a descriptive edit summary and save the edit.
#*Open the new (destination) article talk page to edit in a new tab.
#*Add template <nowiki>{{Copied|from=|from_oldid=|to=|to_diff=}}</nowiki> to the new article talk page, and paste the diff into it, add the title of the source page and the date, add a descriptive edit summary and save the edit.
#(Optionally) Put wikiproject tags on the new article's talk page.
#(If possible) Connect the new article to any corresponding articles in other Wikipedias{{snd}}see [[Wikipedia:Interwiki|Interwiki]].

==Templates==
{{main|Wikipedia:Template messages/Splitting}}
There are a number of templates that can be used on articles and their talk pages as part of splitting articles.

==Articles nominated for splitting==
A list of articles that have been tagged for consideration for splitting are at [[:Category:Articles to be split]].
{{clear}}
{{Splitting progress}}
{{clear}}

==See also==

* [[Wikipedia:Proposed article splits]]
* [[Wikipedia:Summary style]]{{snd}}do this
* [[Wikipedia:Merging]]{{snd}}or this
* [[Wikipedia:Content forking]]{{snd}}don't do this
* [[Wikipedia:Naming conventions (long lists)]]{{snd}}for lists split into multiple pages
* [[Lumpers and splitters]]

{{Splitting templates|nocat=true}}

[[Category:Wikipedia how-to|Splitting]]
[[Category:Wikipedia splitting]]