Grammar Tips: When to Use the Hyphen, En Dash, or Em Dash

The hyphen, the em dash, and the en dash are all easy to confuse. They are all lines used for punctuation, but they vary in length. Many writers mistakenly think they are interchangeable. They serve different purposes, however.

The hyphen is the shortest of the three. It primarily serves to separate numbers (account numbers, phone numbers, etc.) and to combine words. For example, two words can be joined by a hyphen to make a compound descriptive word such as brother-in-law or runner-up. Two or more words used together to form one adjective also use a hyphen (examples: long-term solution, up-to-date itinerary).

The em dash is a long dash used in punctuation. This is what most writers refer to as simply a dash. The em dash has many uses. It can be used to replace parentheses, commas, colons, or quotation marks in a sentence. The em dash is used when the writer needs a stronger break for emphasis and is also helpful when the sentence would be more complicated to read if other forms of punctuation were used. (Parentheses can be used to offset information that is considered less important than or an additional thought added to other information in the sentence or paragraph.) An em dash can be used to draw attention to that information.

Example: We bought dog food, leashes, and dog collars—items that were all requested by the shelter—while we were shopping at the new pet store. The pet store (the one by our school) had all of these items on sale.

The em dash can also be used to set apart a list at the beginning of a sentence; a colon is used if the list falls at the end of a sentence.

Example: Napkins, paper plates, and cups—these are the things I still need for the class party. I also still need several things for the picnic: chips, drinks, and cookies.

The em dash can all be used to mark a change in thought.

Example: I’m ready for—oh, wait, I forgot that we can’t go tonight.

En dashes are shorter than em dashes, but they are longer than hyphens. The en dash is used to replace the word “through.” We use this dash when writing a span of dates or numbers. Example: The camp runs June–August. You can still attend our programs May 10–18.

Most keyboards do not have an em dash or an en dash. You will have to refer to your word processing program to determine how to enter them into a paper. Most programs have shortcuts that will insert them. They should all be used without a space before or after them (unless you are using the hyphen as a minus sign).