Whatever you type into the search box is called the "search string". It may also be referred to as the "search query".

A basic search string is simply the topic you are interested in reading about. A direct match of a basic search string will navigate you directly to Wikipedia's article that has that title. A non-match, or any other type of search string will take you to Wikipedia's search results page, where the results of your search are displayed.

Terms in the search string are subject to stem matching, except for anything included between double quotation marks.

You can include in your search string special characters and parameters that activate specific search capabilities. Using any of these will take you to Wikipedia's search results page with the results of your search displayed.

The maximum search string is 300 characters long.^[1]

The format of the text that is entered is called search string syntax.

Search is case insensitive, that is, upper and lowercase is ignored.

Search "folds" character families, matching similar-looking letters across alphabets, to match foreign terms. So, you don't have to type in diacritical letters, and your terms will still match. For example, Citroen will match Citroën, and Aeroskobing matches Ærøskøbing.

Characters that are not numbers or letters (punctuation marks, brackets and slashes, math and other symbols) are generally ignored. For example, Credit (finance) will return articles with the words credit and finance, ignoring the parentheses, unless an article with exact title Credit (finance) exists. Similarly, a search for the string |LT| (letters LT between two pipe symbols) will only return articles with lt. In order to search for terms that contain non-alphanumeric characters, a regex search must be used instead (using the \ escape character if required), for example insource:/\|LT\|/ will successfully return all instances of |LT|.

The source text is what is searched, which is not always what is displayed on the screen. This distinction is relevant for piped links, for interlanguage links (to find links to Chinese articles, search for zh, not for Zhongwen), special characters (if ê is coded as ê it is found searching for ecirc), etc.

For regex searches, see the insource: parameter below.

Namespace

The default search domain is the article space, but any namespace may be specified in a query.

At the search results page, any number of namespaces can be specified, and users can keep those namespaces as their own default search domain. Partial namespace searches can be made by specifying the initial letters of a page name.

Spaces

The use of spaces is, in general, intuitive. Unnecessary spaces, and all non-alphanumeric characters except " are ignored, which makes for flexibility; it is simplest and best to avoid typing unnecessary spaces, although the tolerance for grey space simplifies copying and pasting search terms without the need for cleanup. For example, credit card is obviously reasonable; copying and pasting [[Credit(?!)card]] is equivalent and convenient; "credit card""payment card" is actually correct and minimal, but "credit card" "payment card" is a sensible equivalent.

Any of the following characters will be treated as a space character: !@#$%^&()_+-=~`{}[]|\:;'<>,.?/. The double quotation mark " is not one of these characters, because it has the special purpose of specifying an exact phrase search, and - and ! can be used to exclude results if either occurs at the beginning of a word or phrase (see more below). We use the term grey-space instead of whitespace here to include the space character itself and all these characters. Multiple [grey-]spaces are equivalent to a single space.

Grey-space is ignored between the words of exact-phrase searches, between adjacent items in the query, and in starting characters of the search box query. All filters can have grey-space between them without affecting search results. Most operators, such as intitle: and incategory:, ignore unnecessary spaces, or grey-space, after the colon.

Where spaces are significant: single search terms cannot have embedded spaces; work space, "work space", and workspace are all different. The particular keywords prefix and insource must be followed immediately by a colon:and their arguments, without intervening [grey-]spaces.

Special characters

For regex searches, see the insource: parameter below.

Double quotes for exact phrase search

 

A phrase can be matched by enclosing it in double quotes, "like this". Double quotes can define a single search term that contains spaces. For example, "holly dolly" where the space is quoted as a character, differs much from holly dolly where the space is interpreted as a logical AND.

Suffixed tilde character for fuzzy search

 

Spelling relaxation is requested by suffixing a tilde (~) like this~, with results like "thus" and "thins". It covers any two character-changes for any character except the first: it returns addition, exchange, or subtraction. This search technique is sometimes called a "sounds-like" search. For example, searching for charlie~ parker~ returns Charlie Parker, Charles Palmer, Charley Parks.

Prefixed tilde character for forced search

 

To force a search rather than navigate directly to a matching page, include a tilde character ~ anywhere in the query. It always takes you to the search results page, never jumping to a single title. For example, the misspelling similiar is redirected to the Similarity article, but prefixing a tilde, ~similiar, lists pages containing that misspelling.

Prefixed hyphen or exclamation point for exclusion H:EXCLUDE

Pages matching a search term can be excluded by prefixing an exclamation point (!) or a hyphen or dash (-) to the term. This is the logical NOT. For example, credit card -"credit card" finds all articles with "credit" and "card" except those with the phrase "credit card".

Wildcard characters

 

The two wildcard characters are * and \?, and both can come in the middle or end of a word. The escaped question mark stands for one character and the star stands for any number of characters. Because many users ask questions when searching, question marks are ignored by default, and the escaped question mark (\?) must be used for a wildcard.

Non-alphabetic characters

For non-alphabetic characters, regex expressions are needed. See #insource: below.

Logical operators

The search engine supports limited boolean logic in searches. Logical NOT (negation) can be indicated by a "-" (minus sign) or a "!" (exclamation point) character prefixed to a search term, or by the NOT keyword.

Parentheses (…) are ignored by the search engine and have no effect.

Search terms are implicitly joined by AND. For example "credit card" housecat searches for pages containing both "credit card" and "housecat". An OR operator is supported, but will only give intuitive results (corresponding to logical disjunction) if all search terms are separated by OR (e.g. red OR green OR blue has the expected behaviour, but red OR green blue does not). OR also does not behave predictably with special keywords (like intitle:) or namespaces. See mw:Help:CirrusSearch/Logical operators for a more detailed explanation.

Parameters

 

Parameters function as name filters, each followed by the search term it operates on. Their search term may be a word or a phrase. The main parameters are namespace:, intitle:, insource:, incategory:, and prefix:. ("namespace" as used here isn't literal – use the name of the actual namespace desired).

"prefix:" differs from the other parameters in that it can only be used at the end of a search string.

A single "namespace:" filter can go first, and a single "prefix" filter can go last.

namespace name:

Only articles are searched by default because most users are only readers. Given only at the beginning of the query, a namespace name followed by a colon limits search results to that namespace. It is a filter without a query string. The namespace can also be selected at Special:Search.

Namespace aliases like WP: or wp: instead of Wikipedia: are accepted.

User: will normally go directly to a user page even if it doesn't exist. To search userspace, use Special:Search or click "Search for pages containing" below the search box.

all: will search all namespaces.

To search multiple namespaces but not all, use "Search in:" at Special:Sea

Prefixing "All:" to a search string, searches all namespaces, and prioritizes mainspace matches to the top.

all:

Using the lower-case "all:" version also searches all namespaces but does not prioritize the results by namespace.

intitle:

Page titles and redirects can be searched with "intitle:query". The search results highlight occurrences in both the title and page content. Multiple "intitle" filters may be used to search for words in titles regardless of order, or possible in different titles (i.e., redirects) for the same article. Regular expressions can be used with "intitle:/regexp/" or the case insensitive "intitle:/regexp/i". See more in the insource section.