The
em dash,
em rule, or
mutton dash or the width of an upper-case "N". The em dash is encoded in Unicode as U+2014 (decimal 8212) and represented in HTML by the named
character entity —.
Usage The em dash is used in several ways. It is primarily used in places where a set of
parentheses or a
colon might otherwise be used, and it can also show an abrupt change in thought (or an interruption in speech) or be used where a
full stop (period) is too strong and a
comma is too weak (similar to that of a semicolon). Em dashes are also used to set off summaries or definitions. Common uses and definitions are cited below with examples.
Colon-like use Simple equivalence (or near-equivalence) of colon and em dash •
Three alkali metals are the usual substituents: sodium, potassium, and lithium. •
Three alkali metals are the usual substituents—sodium, potassium, and lithium. Inversion of the function of a colon • These are the colors of the flag: red, white, and blue. • Red, white, and blue—these are the colors of the flag.
Parenthesis-like use Simple equivalence (or near-equivalence) of paired parenthetical marks • Compare parentheses with em dashes: •
Three alkali metals (sodium, potassium, and lithium) are the usual substituents. •
Three alkali metals—sodium, potassium, and lithium—are the usual substituents. • Compare commas, em dashes and parentheses (respectively) when no internal commas intervene: •
The food, which was delicious, reminded me of home. •
The food—which was delicious—reminded me of home. •
The food (which was delicious) reminded me of home. Subtle differences in punctuation It may indicate an interpolation stronger than that demarcated by parentheses, as in the following from
Nicholson Baker's
The Mezzanine (the degree of difference is subjective). • "At that age I once stabbed my best friend, Fred, with a pair of pinking shears in the base of the neck, enraged because he had been given the comprehensive sixty-four-crayon Crayola box—including the gold and silver crayons—and would not let me look closely at the box to see how Crayola had stabilized the built-in crayon sharpener under the tiers of crayons."
Interruption of a speaker Interruption by someone else • "But I'm trying to explain that I—" "I'm aware of your mitigating circumstances, but your negative attitude was excessive." In a related use, it may visually indicate the shift between speakers when they overlap in speech. For example, the em dash is used this way in
Joseph Heller's
Catch-22: • "He was Cain, Ulysses, the Flying Dutchman; he was Lot in Sodom, Deirdre of the Sorrows, Sweeney in the nightingales among trees. He was the miracle ingredient Z-147. He was— "Crazy!" Clevinger interrupted, shrieking. "That's what you are! Crazy!""—immense. I'm a real, slam-bang, honest-to-goodness, three-fisted humdinger. I'm a bona fide supraman."
Self-interruption • Simple revision of a statement as one's thoughts evolve on the fly: • "I believe I shall—
no, I'm going to do it." • Contemplative or emotional trailing off (usually in
dialogue or in
first person narrative): • "I sense something; a presence I've not felt since—" in
Star Wars Episode IV: A New Hope. • "Get out or else—" : Either an
ellipsis or an em dash can indicate
aposiopesis, the
rhetorical device by which a sentence is stopped short not because of interruption, but because the speaker is too emotional or pensive to continue. Because the ellipsis is the more common choice, an em dash for this purpose may be ambiguous in expository text, as many readers would assume interruption, although it may be used to indicate great emotion in dramatic
monologue. • Long pause: • In
Early Modern English texts and afterward, em dashes have been used to add long pauses (as noted in Joseph Robertson's 1785
An Essay on Punctuation): ::
Quotation Quotation mark–like use This is a
quotation dash. It may be distinct from an em dash in its coding (see
horizontal bar). It may be used to indicate turns in a dialogue, in which case each dash starts a paragraph. It replaces other quotation marks and was preferred by authors such as
James Joyce: : —O saints above! miss Douce said, sighed above her jumping rose. I wished I hadn't laughed so much. I feel all wet. : —O, miss Douce! miss Kennedy protested. You horrid thing!
Attribution of quote source • Inline quotes: •
A penny saved is a penny earned. —
Benjamin Franklin • Block quotes:
Redaction An em dash may be used to indicate omitted letters in a word redacted to an initial or single letter or to
fillet a word, by leaving the start and end letters whilst replacing the middle letters with a dash or dashes (for
censorship or simply
data anonymization). It may also censor the end letter. In this use, it is sometimes doubled. •
It was alleged that D—— had been threatened with blackmail. Three em dashes might be used to indicate a completely missing word. which is similar to the use of
Typographic details Spacing and substitution According to most American sources (such as
The Chicago Manual of Style) and some British sources (such as
The Oxford Guide to Style), an em dash should always be set closed, meaning it should not be surrounded by spaces. But the practice in some parts of the English-speaking world, including the style recommended by
The New York Times Manual of Style and Usage for printed newspapers and the
AP Stylebook, sets it open, separating it from its surrounding words by using spaces or
hair spaces (U+200A) when it is being used parenthetically. The
AP Stylebook rejects the use of the open em dash to set off introductory items in lists. The "space, en dash, space" sequence is the predominant style in German and French
typography. (See
En dash versus em dash below.) In Canada,
The Canadian Style: A Guide to Writing and Editing,
The Oxford Canadian A to Z of Grammar, Spelling & Punctuation: Guide to Canadian English Usage (2nd ed.),
Editing Canadian English, and the
Canadian Oxford Dictionary all specify that an em dash should be set closed when used between words, a word and numeral, or two numerals. The Australian government's
Style Manual for Authors, Editors and Printers (6th ed.), also specifies that em dashes inserted between words, a word and numeral, or two numerals, should be set closed. A section on the 2-em rule (⸺) also explains that the 2-em can be used to mark an abrupt break in direct or reported speech, but a space is used before the 2-em if a complete word is missing, while no space is used if part of a word exists before the sudden break. Two examples of this are as follows: • I distinctly heard him say, "Go away or I'll ——". • It was alleged that D—— had been threatened with blackmail.
Approximating the em dash with two or three hyphens When an em dash is unavailable in a particular
character encoding environment—as in the
ASCII character set—it has usually been
approximated as consecutive double (--) or triple (---) hyphen-minuses. The two-hyphen em dash proxy is perhaps more common, being a widespread convention in the
typewriting era. (It is still described for hard copy manuscript preparation in
The Chicago Manual of Style as of the 16th edition, although the manual conveys that typewritten manuscript and copyediting on paper are now dated practices.) The three-hyphen em dash proxy was popular with various publishers because the sequence of one, two, or three hyphens could then correspond to the hyphen, en dash, and em dash, respectively. Because early comic book
letterers were not aware of the typographic convention of replacing a typewritten double hyphen with an em dash, the double hyphen became traditional in American comics. This practice has continued despite the development of computer lettering.
Usage in AI-generated text In April 2025,
Rolling Stone reported on the growing perception that the em dash is a hallmark of AI-generated writing, particularly by
ChatGPT. The article noted how this idea spread through social media, where users began referring to it as the "ChatGPT hyphen" and how these users advised avoiding it to appear more human. However, several writers defended the em dash as a legitimate and expressive punctuation mark with a long history in human writing.
New York Times Magazine editor Nitsuh Abebe has theorized that growing unfamiliarity with em dashes represents writing conceptually shifting from edited media toward casual emails and text messages. An
OpenAI spokesperson stated that while ChatGPT may favor the em dash, its style depends on prompts and is not a reliable indicator of machine authorship. == En dash versus em dash == , the en dash is actually shorter than the hyphen. The en dash is wider than the
hyphen but not as wide as the em dash. An
em width is defined as the point size of the currently used font, since the M character is not always the width of the point size. In running text, various dash conventions are employed: an em dash—like so—or a spaced em dash — like so — or a spaced en dashlike socan be seen in contemporary publications. Various style guides and national varieties of languages prescribe different guidance on dashes. Dashes have been cited as being treated differently in the US and the UK, with the former preferring the use of an em dash with no additional spacing and the latter preferring a spaced en dash. As examples of the US style,
The Chicago Manual of Style and
The Publication Manual of the American Psychological Association recommend unspaced em dashes. Style guides outside the US are more variable. For example,
The Elements of Typographic Style by Canadian typographer
Robert Bringhurst recommends the spaced en dashlike soand argues that the length and visual magnitude of an em dash "belongs to the padded and corseted aesthetic of Victorian typography". In the United Kingdom, the spaced en dash is the house style for certain major publishers, including the
Penguin Group, the
Cambridge University Press, and
Routledge. However, this convention is not universal. The
Oxford Guide to Style (2002, section 5.10.10) acknowledges that the spaced en dash is used by "other British publishers" but states that the
Oxford University Press, like "most US publishers", uses the unspaced em dash. ''
Fowler's Modern English Usage, saying that it is summarising the New Hart's Rules'', describes the principal uses of the em dash as "a single dash used to introduce an explanation or expansion" and "a pair of dashes used to indicate asides and parentheses", without stipulating whether it should be spaced but giving only unspaced examples. The en dashalways with spaces in running text when, as discussed in this section, indicating a parenthesis or pauseand the spaced em dash both have a certain technical advantage over the unspaced em dash. Most typesetting and word processing expects word spacing to vary to support
full justification. Alone among punctuation that marks pauses or logical relations in text, the unspaced em dash disables this for the words it falls between. This can cause uneven spacing in the text, but can be mitigated by the use of
thin spaces,
hair spaces, or even
zero-width spaces on the sides of the em dash. This provides the appearance of an unspaced em dash, but allows the words and dashes to break between lines. The spaced em dash risks introducing excessive separation of words. In full justification, the adjacent spaces may be stretched, and the separation of words further exaggerated. En dashes may also be preferred to em dashes when text is set in narrow columns, such as in newspapers and similar publications, since the en dash is smaller. In such cases, its use is based purely on space considerations and is not necessarily related to other typographical concerns. On the other hand, a spaced en dash may be ambiguous when it is also used for ranges, for example, in dates or between geographical locations with internal spaces. == Horizontal bar ==