This page contains an overview of the key issues concerning article size. There are three related measures of an article's size:

• Readable prose size: the amount of viewable text in the main sections of the article, not including tables, lists, or footer sections.
• Wiki markup size: the amount of text in the full page edit window, as shown in the character count of the edit history page.
• Browser page size: the total size of the page as loaded by a web browser.

The article size impacts usability in multiple ways:

• Reader issues, such as attention span, readability, organization, information saturation, etc. (when articles are large); and fragmentation and duplication of related information the reader may be seeking over multiple pages (when articles are short).
• Maintenance, such as articles becoming time-consuming to maintain when they are very long; and articles becoming time-consuming to maintain when duplicate or coordinated information, possibly with duplicate references, must be maintained across multiple short articles.
• Technical issues, such as size limits imposed by the MediaWiki software.

When an article is too large, consider breaking it into smaller articles, spinning part of it out into a new article, or merging part of it into another existing article. When an article is too small, consider merging with one or more other existing articles. Such editorial decisions require consensus. Guidelines on the size of articles, and detailed solutions, are provided below. The licensing policy mandates that whenever any content is copied from one article to another new or existing article, an edit summary containing the required copy attribution must be used.

Each Wikipedia article is in a process of evolution and is likely to continue growing. Other editors will add to articles when you are done with them. Wikipedia has practically unlimited storage space; however, long articles may be more difficult to read, navigate, and comprehend. An article longer than one or two pages when printed should be divided into sections to ease navigation (see Wikipedia:Manual of Style and Wikipedia:Layout for guidance). For most long articles, division into sections is natural anyway. Readers of the mobile version of Wikipedia can be helped by ensuring that sections are not so long or so numerous as to impede navigation.

A page of about 10,000 words takes between 30 and 40 minutes to read at average speed, which is close to the attention span of most readers. Understanding of standard texts at average reading speed is around 65%. At 10,000 words it may be beneficial to move some sections to other articles and replace them with summaries per Wikipedia:Summary style – see § Size guideline below.

Articles that cover particularly technical subjects should, in general, be shorter than articles on less technical subjects. While expert readers of such articles may accept complexity and length provided the article is well written, the general reader requires clarity and conciseness. There are times when a long or very long article is unavoidable, though its complexity should be minimized. Readability is a key criterion: an article should have clear scope, be well organized, stay on topic, and have a good narrative flow.

Readable prose is the main body of the text, excluding material such as footnotes and reference sections ("see also", "external links", bibliography, etc.), diagrams and images, tables and lists, Wikilinks and external URLs, and formatting and mark-up. The measure may substantially underestimate the amount of content in articles that summarize much of their information in tables, especially when these contain notes and explanations in text columns.

XTools shows prose information, including number of characters (under "Prose" in the "General statistics" section). It may be used for an article currently being looked at by selecting the View History tab for the page, then Page Statistics from the line near the top headed External Tools. The prosesize gadget is also helpful for estimating readable prose size.

Lists, tables, and other material that is already in summary form may not be appropriate for reducing or summarizing further by the summary style method. If there is no "natural" way to split or reduce a long list or table, it may be best to leave it intact, and a decision made to either keep it embedded in the main article or split it off into a stand-alone page. Regardless, a list or table should be kept as short as is feasible for its purpose and scope. Too much statistical data is against policy.

Wikipedia articles are in constant need of maintenance. This ranges from minor edits correcting spelling and grammar, to major updates reflecting new events and new source material. Some articles may require being rewritten after some time, especially articles created about recent events. It is generally good practice to ensure that articles do not become too long to maintain, especially articles in need of frequent updating. Maintenance can become more difficult when the amount of text on a topic grows, especially when information, possibly with duplicate references, must be maintained across multiple articles.

Total article size should be kept reasonably low, particularly for readers using slow internet connections or mobile devices or who have slow computer loading. Some large articles exist for topics that require depth and detail, but typically articles of such size are split into two or more smaller articles. For notes on unrelated problems that various web browsers have with MediaWiki sites, and for a list of alternative browsers you can download, see Wikipedia:Browser notes.

The maximum limit for Wikipedia is via the MediaWiki software's wgMaxArticleSize to 2 MiB (specifically, 2048 kibibytes or 2,097,152 bytes). Exceeding the post-expand limit will result in templates in the article appearing incorrectly.

Some useful rules of thumb for splitting, trimming or merging articles:

Word count	What to do
> 15,000 words	Almost certainly should be divided or trimmed.
> 9,000 words	Probably should be divided or trimmed, though the scope of a topic can sometimes justify the added reading material.
> 8,000 words	May need to be divided or trimmed; likelihood goes up with size.
< 6,000 words	Length alone does not justify division or trimming.
< 150 words	If an article or list has remained this size for over two months, consider merging it with a related article. Alternatively, the article could be expanded; see Wikipedia:Stub.

Please note: These rules of thumb are intended to be approximate and apply only to readable prose – not to wiki markup size (as found on history lists or other means). Word counts can be found with the help of Shubinator's DYK tool or Prosesize gadget (either as a script or on web version), or by copying and pasting the text (not including references) to a word processor or other tool on your computer that can count words. The latter method is more accurate for stand-alone lists and articles with significant list content, as the other tools do not count words in image captions, lists, or tables. When considering splitting lists, consider the impact of breaking up a sortable table.

The rules of thumb apply somewhat less to disambiguation pages and naturally do not apply to redirects.

The appropriate length of the lead section depends on the total length of the article. Most leads of featured articles are 250–400 words.

Very large articles should be split into logically separate articles. Long stand-alone list articles are split into subsequent pages alphabetically, numerically, or subtopically. Also consider splitting and transcluding the split parts (for example with Template:Excerpt).

When splitting a section into a new article, you should refer to the steps in WP:PROPERSPLIT, including an edit summary in the new article attributing the origin of the content to the existing article.

There is no need for haste in splitting an article when it starts getting large. Sometimes an article simply needs to be big to give the subject adequate coverage. If uncertain, or with high-profile articles, start a discussion on the talkpage regarding the overall topic structure. Determine whether the topic should be treated as several shorter articles and, if so, how best to organize them. If the discussion makes no progress consider adding one of the split tags in order to get feedback from other editors.

A relatively trivial topic may be appropriate in the context of the larger article, but inappropriate as the topic of an entire article in itself. In most cases, it is a violation of the neutral point of view policy to specifically break out a controversial section without leaving an adequate summary. It also violates that policy to create a new article specifically to contain information that consensus has rejected from the main article. Consider other organizational principles for splitting the article, and be sure that both the title and content of the broken-out article reflect a neutral point of view.

If a section of an article is a magnet for unhelpful contributions (such as the "external links" section or trivia sections), be aware that while moving it to another article may help to clean up the main article, it creates a new article that consists entirely of a section for unwanted contributions. If an article includes large amounts of material not suitable for inclusion in the encyclopedia, it is better to remove that content than to create a new article for it.

Text can often be trimmed to use fewer words to say the same thing; Some good essays have been written on how to do this, including WikiProject Military history's Copy-editing essentials, User Tony1's redundancy exercises and the Wikipedia:Principle of Some Astonishment. This technique not only leads to (slightly) shorter articles, readability of those articles typically improves.

Removing appropriate content, especially summary style, and/or reliably sourced and non-tangential information, from an article simply to reduce length without moving that content to an appropriate article either by merging or splitting, may require a consensus discussion on the talk page; see Wikipedia:Content removal § Reasons for acceptable reasons.

Markup or markup language is the code used to organise a document and make it readable. Wiki markup is the codes used on Wikipedia. Markup size includes readable prose, the wiki codes, and any media used in the article, such as images or audio clips.

You can find the size of the markup of a page in bytes from its page history (near the bottom). Also the search box entry: intitle:Article title will show both number of words in the article and the size of the article in kilobytes. In most cases these are not reliable indications on their own of whether an article should be split.

The largest articles by markup size are listed at Special:Longpages.

Note that the ability to edit a section rather than the entire page decreases wait time, removing some of the many, oversized-page problems for editors; however, readers with slow connections will still have to wait for the entire page to load.

If you have encountered an article that is so long you can't edit it, or if your browser chops off the end of the article when you try to edit it, there are a few ways you can solve the problem.

Often, you can edit the article one section at a time by using the "Edit" links you see next to each header in the article. You can edit the article lede before the first section by appending &section=0 to the URL. (See T2156 and two JavaScript workarounds: 1, 2.) You can insert a new section either by using the "New section" link (if there is one) in the "Views" section, or by editing an existing section and explicitly adding a second header line within it. If you find a section that is itself too long to edit, you can post a request for assistance on the help desk.

• {{section length}}, returns the length of a given section, or the article
• Help:Template limits
• Phab:T248796 (Mobile formatter breaks past 1000 images)
• Special:LongPages
• Wikipedia:Article series
• Wikipedia:Database reports/Featured articles by size (prose size and word count)
• Wikipedia:Database reports/Long pages
• Wikipedia:Database reports/Long stubs
• Wikipedia:Database reports/Talk pages by size
• Wikipedia:Featured articles/By length (in bytes)
• Wikipedia:Out of scope
• Wikipedia:Too much detail
• Wikipedia:Words per article
• Wikipedia:Writing better articles#Stay on topic
• Preferences → Gadgets → Browsing → Prosesize: add a toolbox link to show the size of and number of words in a page (direct link), and then save.