A Guide to Em Dashes, En Dashes, and Hyphens

Be dashing—and do it well

Among punctuation marks, dashes have a certain panache. They take the reader aside, and then draw that reader to the next bit like a good dance partner in the lead.

There are various punctuation items that can be described as dashes, and we will get to them all, but we’ll begin with the most useful, and most used. It looks like — or sometimes (as when one’s word processing program fails to convert it) - - and it’s called the “common dash,” or “em dash.” The two names are well-earned; this dash is the most common true dash, and it’s the approximate width of a capital M.

The Em Dash: An Introduction

The em dash can function like a comma, a colon, or parenthesis. Like commas and parentheses, em dashes set off extra information, such as examples, explanatory or descriptive phrases, or supplemental facts. Like a colon, an em dash introduces a clause that explains or expands upon something that precedes it.

The em dash is sometimes considered a less formal equivalent of the colon and parenthesis, but in truth it’s used in all kinds of writing, including the most formal—the choice of which mark to use is really a matter of personal preference.

Spacing around an em dash varies. Most newspapers insert a space before and after the dash, and many popular magazines do the same, but most books and journals omit spacing, closing whatever comes before and after the em dash right up next to it. This website prefers the latter, its style requiring the closely held em dash in running text.

How to type one, however, depends on your machine.

The Em Dash in Action: A New Direction

• An em dash can mark an abrupt change or break in the structure of a sentence.

Mabel the Cat was delighted with the assortment of pastries the new bakery featured, but Harry the Dog—he felt otherwise.

• An em dash can indicate interrupted speech or a speaker’s confusion or hesitation.

Harry’s bafflement was apparent. “That the bakers fail to recognize the crucial importance of the cheese Danish—”

“Of course you have a point,” Mabel murmured. “That is—I suppose it is concerning.”

The Em Dash in Action: Attention Must Be Paid

• Em dashes are used in place of commas or parentheses to emphasize or draw attention to parenthetical or amplifying material. In this particular task, em dashes occupy a kind of middle ground among the three: when commas do the job, the material is most closely related to what’s around it, and when parentheses do the job, the material is most distantly related to what’s around it; when dashes do the job the material is somewhere in the middle.

The butteriness of the pastries did say something about an appropriate level of commitment to decadence—at least there was that.

And the wide range of its hours of operation—6 a.m. to 6 p.m.—certainly showed concern for customers’ manifold circumstances.

• Dashes set off or introduce defining phrases and lists.

A regular selection of three kinds of croissants—plain, almond, and chocolate—was heartening, both Mabel and Harry agreed.

The pies changed—apple year-round, for example, but pumpkin in fall and winter, strawberry rhubarb in spring, and peach in summer—as the bakery’s devotion to fresh ingredients dictated.

And Harry was extremely pleased to see the selection of available cakes—both chocolate and yellow butter cake; carrot cake; pound cake; lemon chiffon; and flourless chocolate cake.

• An em dash is often used in place of a colon or semicolon to link clauses, especially when the clause that follows the dash explains, summarizes, or expands upon the preceding clause in a somewhat dramatic way.

Harry would never forget the Tuesday that Mabel called him from the bakery, her voice brimming with excitement—the bakery had added cheese Danishes to its selection.

Nor would Harry forget his first bite of the Danish she delivered to him. It was revelatory—it was a cheese Danish nonpareil.

• An em dash or pair of dashes often sets off illustrative or amplifying material introduced by such phrases as for example, namely, and that is, when the break in continuity is greater than that shown by a comma, or when the dash would clarify the sentence structure better than a comma.

The bakery was truly phenomenal. Although they did miss the mark somewhat with the pineapple upside-down cake Mabel ordered—that is, the cake had clearly been baked right-side up.

”You see,” Mabel averred, “even a moderately keen observer can ascertain—namely from its shape—a baked cake’s oven orientation.”

• An em dash may introduce a summary statement that follows a series of words or phrases.

Chocolate chip, oatmeal raisin, peanut butter, snickerdoodle, both macarons and macaroons—the panoply of cookie varieties was impressive as well.

The bakery was also adept at deliciously modifying recipes to meet any variety of dietary restrictions—not an easy feat in many cases.

• A dash often precedes the name of an author or source at the end of a quoted passage—such as an epigraph, extract, or book or film blurb—that is not part of the main text. The attribution may appear immediately after the quotation or on the next line.

“One cannot underestimate the effect a good bakery can have on a person’s well-being.” —Mabel the Cat, The Websterburg Reporter

The bread sublime, the cheese Danish divine.
—Harry the Dog

The Em Dash in the Company of Other Punctuation Marks

• If an em dash appears at a point where a comma could also appear, the comma is omitted.

Within its first year, Mabel and Harry had sampled all of the bakery’s offerings—all 62 items—and had also decided that the exercise was worth repeating.

When the bakery closed for the month of August to give its staff a break—no one denied it was much deserved—Mabel was forlorn.

• When a pair of em dashes sets off material ending with an exclamation point or a question mark, the mark is placed inside the dashes.

Mabel tried, despite her dolefulness—for how could she be otherwise?—to bake her own bread but each loaf that emerged from her oven tasted vaguely of tears.

When September arrived—finally!—the yeasty perfume wafting through Websterburg’s town square routed her darksome gloom.

• Dashes are used inside parentheses, and vice versa, to indicate parenthetical material within parenthetical material. The second dash is omitted if it would immediately precede the closing parenthesis; a closing parenthesis is never omitted.

The bakery’s reputation for scrumptious goods (ambrosial, even—each item was surely fit for gods) spread far and wide.

The Other Dashes (Not Nearly So Dashing But Still Useful)

• Remembering that the em dash is the length of a capital M, it will surprise no one that the so-called “en dash” is the approximate length of a capital N, –. The en dash is the least loved of all; it’s not easily rendered by the average keyboard user (one has to select it as a special character, whereas the em dash can be conjured with two hyphens), so it’s mostly encountered in typeset material. (A hyphen does its job in other text.) It is most often used between numbers, dates, or other notations to signify “(up) to and including.”

The bakery will be closed August 1–August 31.

The bakery is open 6:00 a.m.–6:00 p.m.

The exceedingly complex recipe spans pages 128–34.

Mabel and Harry lived elsewhere 2007–2019.

Note that one does not need words like from and between in these cases. The phrase “open 6:00 a.m.–6:00 p.m.” can be read as “open between 6:00 a.m. and 6:00 p.m.” or as “open from 6:00 a.m. to/until 6:00 p.m.”

• If you want to be official about things, use the en dash to replace a hyphen in compound adjectives when at least one of the elements is a two-word compound.

the post–Cold War era

The thinking is that using a hyphen here, as in “the post-Cold War era,” risks the suggestion that post attaches only to Cold. It’s unlikely, though, that a reader would truly be confused.

• The en dash replaces the word to between capitalized names, and is used to indicate linkages such as boundaries, treaties, and oppositions.

a Boston–Washington train

the Websterburg–Oxfordville border

the pie–cake divide

night–day differences or night-day differences

• A two-em dash, ——, is used to indicate missing letters in a word and, less frequently, to indicate a missing word.

The butter-stained and crumb-embedded note was attributed to a Ms. M—— of Websterburg.

• A three-em dash, ———, indicates that a word has been left out or that an unknown word or figure is to be supplied.

Years later it was revealed that the Websterburg bakers had once had a bakery in ———, a city to the south. But the water quality there was prohibitive to the creating of decent bagels.

A Hyphen Can Be Considered to Be a Kind of Dash

While we said above that the em dash, also called the “common dash,” is the most common of the true dashes, hyphens show up more frequently in text. They have a variety of uses.

• Hyphens are used to link elements in compound words.

the bakery fan club’s secretary-treasurer

a baker-owner

• In some words, a hyphen separates a prefix, suffix, or medial element from the rest of the word.

Websterburg’s pre-bakery days

a bread-like scone

jack-o'-lantern sugar cookies

• As we noted above, a hyphen often does the job of an en dash between numbers and dates, providing the meaning "(up) to and including."

pages 128-34

the years 2007-2019

• A hyphen marks an end-of-line division of a word.

Mabel and Harry don’t like to linger on their memories of Webster-
burg’s pre-bakery days.

• A hyphen divides letters or syllables to give the effect of stuttering, sobbing, or halting speech.

"M-m-mabel, the cheese Danish is divine!”

• Hyphens indicate a word spelled out letter by letter.

Let’s not even talk about August, when the bakery is c-l-o-s-e-d.

https://www.merriam-webster.com/words-at-play/em-dash-en-dash-how-to-use