Hyphen vs. Dash: How to Use Hyphens and Dashes

A hyphen (-) is a punctuation mark resembling a short horizontal line. Use it to combine compound words. The hyphen has its own unique key on a standard QWERTY computer keyboard. You can create a hyphen by pressing the hyphen key.

The use of the hyphen changes depending on the context of the sentence.

1. 1. Compound numbers: Use a hyphen to type compound numbers containing two digits. Examples include "thirty-six" and "eighty-five." Hyphens can also fit in longer numbers such as "ninety-nine thousand one hundred twenty-one."
2. 2. Compound nouns: Many (but not all) compound nouns use hyphens to connect their individual words to create new words. Examples include "singer-songwriter" and "mother-in-law."
3. 3. Compound modifiers: Some modifying phrases use hyphens, such as "best-in-class" or "eight-year-old." Use hyphens with compound modifiers that come before a noun ("a centuries-old text") but not those that come after nouns ("the text was centuries old"). Hyphens do not belong in a compound adjective where the first word is an adverb ("oddly delicious"). Hyphens can also allow you to combine prefixes that end in a vowel and words that begin with a vowel (“pre-owned”).
4. 4. Unfinished words: When spacing is a concern and a word won’t fit at the end of a line of text, a hyphen can indicate that the rest of the word will continue on the following line. This is less of a concern in the context of writing emails or digital text, but it comes into play when formatting books and magazines or even writing letters by hand.

No fixed rules exist for which compound words receive hyphenation and which do not. The spell-check functions on some word processors can help flag mistakes or inconsistencies. When in doubt, consult a formal writing style guide, such as the Chicago Manual of Style for essays or the American Psychological Association (APA) grammar guide for scientific papers.

A dash is a punctuation mark that looks like an elongated hyphen. Unlike the hyphen, which mainly serves to create compound words, the dash has a variety of uses depending on the type of dash.

There are two types of dashes found in the English language.

1. 1. En dash: Also known as an N-dash (–), this punctuation mark is so named because it is as wide as the letter N. On a PC computer, you can type an en dash by typing "ctrl + the minus sign." On a Mac, you use "option + the hyphen key."
2. 2. Em dash: Also called an M-dash (—), this punctuation mark is as wide as an uppercase M. It can be typed on a PC with “alt + ctrl + the minus sign.” On a Mac, type "option + shift + the hyphen key."

An en dash appears in three ways in standard English grammar.

1. 1. To separate ranges of numbers: Examples include "class runs from 4–6 pm" or "the Orioles won 7–4."
2. 2. To combine related nouns or directional adjectives: Examples include "the Detroit–Chicago game" or "East–West Highway." Choosing an en dash over a hyphen, in this case, is less of a rule and more of a stylistic preference.
3. 3. To create complex compound adjectives: Examples include “Pulitzer Prize–winning journalist” or “post–World War II era.” This is also less of a rule and more of a stylistic preference.

The em dash exists in English punctuation to separate a phrase or clause from the rest of a sentence. You can use em dashes much as you might use parentheses or commas. The em dash can even be used like a semicolon or colon in the sense that a single dash can set off a phrase at the end of a sentence.

Examples of a properly used em dash include:

• Mr. Jackson—who taught three generations of my family—is finally retiring.
• I bought some supplies—wood, screws, a hammer, and glue—at the hardware store.
• I ran into the one person I was avoiding—Carol.

The em dash does not require spacing from the words that precede and follow it. However, depending on your preference, you may wish to use spaces before and after the em dash. Either style works so long as you maintain consistency.

The differences between hyphens, en dashes, and em dashes are relatively straightforward.

• Hyphens: Use a hyphen to make a compound word, number, or adjective ("fifty-nine,” “last-minute,” and "full-service").
• En dashes: Use slightly longer en dashes to separate numbers ("a score of 8–3"), proper nouns ("the Michigan–Ohio State rivalry" or "the Dodd–Frank bill"), or related nouns having to do with direction (“East–West Highway”).
• Em dashes: Use long em dashes in place of other punctuation—particularly commas and parentheses—to set apart key phrases or clauses.

Become a better writer with the MasterClass Annual Membership. Gain access to exclusive video lessons taught by the world’s best, including Neil Gaiman, Walter Mosley, Margaret Atwood, Joyce Carol Oates, Dan Brown, and more.