This is a Wikipedia guideline for placing redirect pages into categories. It is intended to document current practice and suggest best practice in other areas, and indicate where categorization of redirects can be misleading.
When to categorize a redirect
Normal ("hard") redirects should be placed in one of several maintenance categories specifically for redirects. This should be done using categorization templates (rcats) such as {{R with Wikidata item}}.
Soft redirects usually should not be categorized by rcats. Use of {{Soft redirect with Wikidata item}} and {{R category with possibilities}} to tag soft-redirected categories are presently the only exceptions.
Redirects are not usually sorted to article categories; however, there are exceptions, as described below.
Categories just for redirects
There are a series of categories that are used only for redirects. Redirects are placed in categories by templates. These categories explain why the redirect exists, for example {{R from merge}} means it was created by a merge or {{R from alternative name}} means that the redirect is an alternative name for the main title.
These categories are only intended to contain redirects, and are helpful in keeping track of redirects and further subcategorizing them as needed. They include both redirects within main namespace and in other namespaces. They are often applied using templates, though such categories can also be created and populated directly. This categorization is intended for Wikipedia editors, not readers.
For tables of redirect category templates, grouped both alphanumerically and by function, see Wikipedia:Template index/Redirect pages. For the categorical list of such templates, see Category:Redirect templates. All the redirect categories are subcategories of Category:Wikipedia redirects, which is not meant to contain any redirects directly and is purposely kept empty except for subcategories.
Article categories
There are some situations where placing a redirect in an article category is acceptable and can be helpful to users browsing through categories. The following are examples of some of these situations:
Redirects having a target that is incompatible with the category
Alternative names should not look out of place on a category page. This is often a way to satisfy disagreements over renaming an article when more than one name seems equally valid. The alternative name(s) becomes a redirect and gets categorized the same way as its target. Another example is when a single article covers things known by multiple names, such as a person who is known in multiple fields of endeavour under different names, a merged article about three different newspapers, or a sketch comedy television show whose name exists on Wikipedia as a redirect to the comedy troupe that created it. In such a case, consideration needs to be given to which title should be reflected in an individual category.
Note that placing such a category on the target article, with the alternative title in pipetext, does not accomplish the desired purpose, as pipetext in a category link only affects how a title is ordered alphabetically, not how it actually appears.
- Examples:
- A Racial Program for the Twentieth Century is a hoax quotation by the phony author Israel Cohen. The redirect to that article, Israel Cohen (hoax), belongs in Category:Nonexistent people used in hoaxes but the article does not.
- Wile E. Coyote and the Road Runner is an article that covers both the cartoon and its titular characters. Categories that refer to one of the characters, but not both—such as Category:Fictional coyotes and Category:Fictional birds—are placed on the appropriate redirects.
Alternative names for articles
The primary function of the category system is to allow readers to browse through articles. The category system is often used like an alphabetical index. It is sometimes helpful for redirects from common alternative names to appear in the index list. Editors should consider whether alternative names should be mixed in with other names, or not. Sometimes an entirely new category is more appropriate (see Categorization of multiple taxonomies below).
Subtopic categorization
Some subtopics of articles have well-known names and, over time, may expand to become separate articles. Many articles cover several topics that have been combined. This can happen following a merge of several related articles. Often there are redirects pointing to these subtopics. These redirects can be categorized. In some cases, the categories for the redirects that point to the subtopics will be different than the categories for the entire article.
- Example of similar categorization:
- Butterfly vertebrae points to a subsection of Congenital vertebral anomaly – both appear in Category:Dog health
- Examples of different categorization:
- Prohibition in Finland (appearing in Category:History of Finland, Category:1932 in Finland, and Category:Prohibition by country) – redirects to a subsection of Prohibition (appearing in Category:Prohibition and Category:Alcohol law)
Categorization of multiple taxonomies
Some articles can be organized by more than one taxonomy. An example of this is the organization of animal and plant articles by common names and binomial name taxonomy. This is possible by categorizing the article one way and categorizing the redirect a different way. In this case, the alternative categorization of the redirect will not appear in the article unless it is manually added.
- Examples:
- An example for plants is: Category:Banksia taxa by common name and Category:Banksia taxa by scientific name.
Categorization of list entries
Some well-organized lists have redirects pointing at their subsections. In such cases, categorization of the redirects can be an alternative way of browsing entries in a long list. It can also provide an alphabetical listing for lists that are not organised alphabetically, such as lists organised in a chronological order. Redirects to sections of minor character lists should generally only be categorized within that fictional setting, and not in the wider fictional categories.
- Examples:
- Category:EastEnders characters provides a single alphabetical listing of both minor and major characters in the soap opera EastEnders. However, the minor character redirects should not be categorized outside the EastEnders category structure, e.g. not in Category:Fictional characters by occupation.