Em Dash vs. En Dash vs. Hyphen: What’s the Difference?

When it comes to proper punctuation, choosing between an exclamation point and a question mark is child’s play. The semicolon-vs.-colon decision is a bit tougher to make. But even that can’t compare to the puzzle of picking the right kind of dash or hyphen to drop into a sentence.

You can blame that difficulty at least partially on how similar they look. As its name suggests, an em dash (—) is roughly the length of the letter M, while an en dash (–) more closely matches an N. A hyphen (-) is shorter still. That said, unless they’re all lined up next to each other, it’s not always easy to identify which one you’re looking at, so it helps to have a handle on which contexts call for which little line.

Em Dash vs. En Dash

In general, a good way to remember whether you need an em dash or an en dash is to ask yourself some version of this question: Are you trying to separate whole parts of a sentence, or link individual terms together?

If the answer is the former, go with an em dash. It’s longer than an en dash—just like the elements you’re separating. When to use an em dash instead of some other punctuation mark is largely up to you. It can take the place of a semicolon, colon, or comma if you’re trying to introduce a new clause with slightly more emphasis or drama. For example: 

My cat has a pretty revolting habit that I wish she’d break—bringing me dead animals.

An em dash can also set apart an aside that you might otherwise distinguish with commas or parentheses. For example:

My cat—not the same one who delivers me dead animals—loves to drown toys in her water bowl.

As Merriam-Webster explains, em dashes are also used for quote attribution, like so:

“Thank you for the mangled mouse corpse!” —Me, to my cat.

And to signify that someone got cut off in the middle of a thought or sentence, as in:

“What’s that you have for me? It looks like a—,” I said, stopping suddenly as I realized the creature clutched between my cat’s jaws was my son’s pet hamster.

An en dash, meanwhile, connects words or numbers that designate a range or score, often replacing the word to. Instead of September to December and chapters 12 to 16, for instance, you can write September–December and chapters 12–16. 

En dashes also come in handy when you’re linking modifiers with open compound words, like New York–style pizza. Since style is modifying New York—not just York—the situation calls for something slightly longer (and therefore stronger) than a hyphen.

En Dash vs. Hyphen

Chicago-style pizza, on the other hand, needs a hyphen. So does any other instance in which you’re only linking a word to the one directly next to it. This includes compound words like old-fashioned and left-handed; longer phrases like merry-go-round and run-of-the-mill; and numbers like twenty-seven and two-thirds.

You should opt for a hyphen over an en dash in these situations, as well:

• To signal that a word is continued on the next line.
• To signal that a word is being spelled out, letter by letter.
• To signal that someone is speaking with a stutter.

But with date and number ranges, it’s not uncommon to see a hyphen rather than an en dash. So you can rest assured that if your favorite team wins the Super Bowl with a final score of 43–8, people probably aren’t going to care which kind of punctuation separates the digits. (Just don’t use an em dash.)

[h/t Merriam-Webster]