Help:Footnotes
This help page is a how-to guide. It details processes or procedures of some aspect(s) of Wikipedia's norms and practices. It is not one of Wikipedia's policies or guidelines, and may reflect varying levels of consensus and vetting. |
This page explains how to create the Footnotes section for Wikipedia articles. In this context, the word "Footnotes" refers to the Wikipedia-specific manner of documenting an article's sources and providing tangential information, and should not be confused with the general concept of footnotes. This how-to does not cover the formatting of citations within the Footnotes section, which is reviewed in Citing sources.
Footnotes are used most commonly to provide:
- references (bibliographic citations) to reliable sources,
- explanatory information, or
- source information for tables and other elements.
Footnotes or shortened footnotes may be used at the editor's discretion in accordance with the guideline on Variation in citation methods.
Only certain types of material on the English Wikipedia are required to have an inline citation. There is no requirement to provide a citation for every sentence, because multiple sentences may be supported by the same footnote. For advice on which material should be cited, see the guidelines on When you must use inline citations, the Good article criteria and When to cite. For advice on how to organize and format bibliographic citations, see the guideline on Citing sources and examples of Citation templates.
Footnotes are created using the Cite software extension. This extension adds the HTML-like elements <ref>...</ref>
, <references />
and <references>...</references>
. The elements are also used in a number of templates; for example, it is becoming more common to use {{reflist}}
rather than <references />
as it can style the reference list.
Overview
The Footnotes system shows two elements on the page:
- A Footnote marker is displayed in the article's content as a bracketed, superscripted number, letter, or word. Examples shown respectively are: [1][a][Note 1]. This footnote label is linked to the full footnote. Clicking on the footnote marker jumps the page down to the footnote and highlights the citation. If you are using the desktop site and have Javascript enabled, then hovering your cursor over a footnote marker (or touching it on touch devices) will show a pop-up box containing the footnote.
- A Footnote displays the full citation for the source. Together the footnotes are displayed in an ordered list wherever the reference list markup {{reflist}} is placed. Each entry begins with the footnote label in plain text. The entire reference list is formatted in a slightly smaller font.
- Each successive footnote label is automatically incremented. Thus the first footnote marker would be [1], the second would be [2] and so on. Custom labels are also incremented: [a][b][c], [Note 1] [Note 2] [Note 3].
- For a single-use footnote, the label is followed by a caret (^) that is a backlink to the matching footnote marker. For example:
- If a named footnote is used in the text multiple times, then the footnote has multiple backlinks shown as letters:
- Clicking on the backlink or pressing Alt+← returns to the footnote marker.
Footnotes in action
The superscript numeral "1" in square brackets at the end of this sentence is an example of a footnote marker.[1]
- ^ This is a footnote that contains a citation or note.
Footnotes: the basics
To create the footnote marker, determine the point in the page content where the marker is desired and enter the markup with the citation or note inside the <ref>...</ref>
tags. For example:
Markup | Renders as |
---|---|
This is page content.<ref>''LibreOffice For Starters'', First Edition, Flexible Minds, Manchester, 2002, p. 18</ref> {{reflist}} |
|
The {{reflist}} template will be explained in the next section.
The content inside the <ref>...</ref>
will show in the reference list. The ref tags can be added anywhere a citation or note is needed. There must be content inside the tags, else an error will show.
Where to place ref tags
Ref tags should follow any punctuation (usually a period), not precede it; see WP:REFPUNC. There should be no space between the punctuation and the tag:
Markup | Renders as |
---|---|
...text.<ref>Content of the reference</ref> {{reflist}} |
|
...text<ref>Content of the reference</ref>. {{reflist}} |
|
...text. <ref>Content of the reference</ref> {{reflist}} |
|
Formatting ref tags
The content of the ref tags can be formatted using most wiki markup or HTML markup, although techniques such as the pipe trick and template substitution will not work in footnotes. For example:
Markup | Renders as |
---|---|
This is page content.<ref>''LibreOffice For Starters'', First Edition, Flexible Minds, Manchester, 2002, p. 18</ref> {{reflist}} |
|
The ref tag content may also contain an internal or external link:
Markup | Renders as |
---|---|
This is page content.<ref>''[http://www.example.org LibreOffice For Starters]'', First Edition, Flexible Minds, Manchester, 2002, p. 18</ref> {{reflist}} |
This is page content.[1]
|
URLs must begin with a supported URI scheme. http://
and https://
will be supported by all browsers; however, ftp://
, gopher://
, irc://
, ircs://
, mailto:
and news:
may require a plug-in or an external application and should normally be avoided. IPv6 host-names are currently not supported.
If URLs in citation template parameters contain certain characters, then they will not display and link correctly. Those characters need to be percent-encoded. For example, a space must be replaced by %20
. To encode the URL, replace the following characters with:
Character | space | " | ' | < | > | [ | ] | { | | | } |
---|---|---|---|---|---|---|---|---|---|---|
Encoding | %20 | %22 | %27 | %3C | %3E | %5B | %5D | %7B | %7C | %7D |
Single apostrophes do not need to be encoded; however, unencoded multiples will be parsed as italic or bold markup. Single curly closing braces also do not need to be encoded; however, an unencoded pair will be parsed as the double closing braces for the template transclusion.
Reference lists: the basics
Once any number of footnotes have been inserted into the content, the reference list must be generated. For the basic reference list, add {{reflist}} wherever the list is desired. Once the page is published and viewed, the footnotes will be automatically generated and numbered and the reference list will be generated. The main reference list is placed in a separate section, usually titled "References", "Notes" or the like.
Markup | Renders as |
---|---|
This is page content.<ref>''LibreOffice For Starters'', First Edition, Flexible Minds, Manchester, 2002, p. 18</ref> ==References== {{reflist}} |
|
Notes
- In some cases, a page has more than one reference list. Until 2014, multiple uses of {{reflist}} on the same page required use of a
|close=
parameter; that bug has been fixed and the|close=
parameter may safely be removed. - When editing,
<references />
may be seen instead of {{reflist}}. This will automatically display the references in multiple columns, but<references />
does not offer the other advanced features of {{reflist}}.
Footnotes: using a source more than once
You can cite the same source more than once on a page by using named references, also called named footnotes. The syntax to define a named footnote is:
<ref name="name">content</ref>
To invoke the named footnote:
<ref name="name" />
Names for footnotes and groups must follow these rules:
- Names are case-sensitive. Please do not use raNdOM capitalization.
- Names must not be purely numeric; the software will accept something like
":31337"
(which is punctuation plus a number), but it will ignore"31337"
(purely numeric). - Names should have semantic value, so that they can be more easily distinguished from each other by human editors who are looking at the wikitext. This means that ref names like
"Nguyen 2010"
are preferred to names like":31337"
. - Names must be unique. You may not use the same name to define different groups or footnotes. Try to avoid picking a name that someone else is likely to choose for a new citation, such as
":0"
or"NYT"
. - Please consider keeping reference names short, simple, and restricted to the standard English alphabet and numerals. If spaces are used, the following technical restrictions become relevant:
- Quotation marks are preferred but optional if the only characters used are letters
A–Z
,a–z
, digits0–9
, and the symbols!$%&()*,-.:;<@[]^_`{|}~
. That is, all printable ASCII characters except#"'/=<>?\
and space. - Inclusion of any other characters, including spaces, requires that the reference name be enclosed in quotes; for example,
name="John Smith"
. But quote-enclosed reference names may not include a less-than sign (<
) or a double straight quote symbol ("
), which may however be included by escaping as<
and"
respectively. - The quote marks must be the standard, straight, double quotation marks (
"
); curly or other quotes will be parsed as part of the reference name.
- Quotation marks are preferred but optional if the only characters used are letters
- You may optionally provide reference names even when the reference name is not required. This makes later re-use of the sourced reference easier.
Note that the colon-followed-by-numeral names, like ":0"
, are currently generated by default in VisualEditor.
Markup | Renders as |
---|---|
This is page content.<ref name="manchester2002">{{cite book|title=LibreOffice for Starters|edition=First|publisher=Flexible Minds|location=Manchester|year=2002|p=18}}</ref> This is more content.<ref name="manchester2002" /> {{reflist}} |
|
The actual name used can be almost anything, but it is recommended that it have a connection to the citation or note. A common practice is to use the author-year or publisher-year for the reference name. This helps editors remember the name, by associating it with the information that is visible to the reader.
Note that the footnote labels are incremented in the order they are used, and that they use the same label when reused, thus the labels can seem out of order:
Markup | Renders as |
---|---|
This is starter content.<ref name="manchester2002">{{cite book|title=LibreOffice for Starters|edition=First|publisher=Flexible Minds|location=Manchester|year=2002|p=18}}</ref> This is expert content.<ref name="lexington2004">{{cite book|title=OpenOffice for Experts|publisher=Lexington|year=2004|p=18}}</ref> And more starter content.<ref name="manchester2002" /> And more expert content.<ref name="lexington2004" /> {{reflist}} |
|
When using both names and groups, the syntax is:
<ref group="groupname" name="name">Content</ref>
Care should be taken when deleting references to avoid creating a cite error. See Avoiding common mistakes.
Reference lists: columns
When using {{Reflist}} or <references />
, the list can be split into columns. The <references />
tag provides a default column width of 30 em. {{Reflist}} can be used to set a different column width:
{{Reflist|xxem}}
, where xx is the column width in em.
The number of columns will automatically be adjusted to the width of the display. It should be used only when necessary, as both the tag and the template have built-in auto-formatting capabilities providing a useful default display in most scenarios.
The set columns feature is now deprecated in favor of the option described above, which is better suited to flexible formatting for a variety of display screen sizes, ranging from mobile phones and tablets to wide-screen "cinema" displays. Forcing a fixed number of columns has been disabled in mobile view.
The number of columns to use is up to the editor, but some major practices include:
{{Reflist|30em}}
: Where there are many footnotes plus a page-width Bibliography subsection: see Ebola virus disease (06:28, 23 June 2013){{Reflist|20em}}
: Where Shortened footnotes are used; see NBR 224 and 420 Classes (13:32, 1 August 2011).
For example:
Using {{Reflist|30em}}
will create columns with a minimum width of 30 em,
Markup | Renders as |
---|---|
Lorem ipsum.<ref>Source name, access date, etc.</ref> Lorem ipsum dolor sit amet.<ref>Source name, access date, etc.</ref> ==References== {{Reflist|30em}} |
|