Em dash vs en dash (and the hyphen)

English has three horizontal marks of different lengths, and each has its own job. They are not interchangeable, even though many keyboards only show one.

See it work

The answer—if there is one—will surprise you.

Em dash (width of an m) — a break in thought.

Type it: Mac Option + Shift + - · Windows Alt + 0151

Hyphen (-)

The shortest. It joins words into compounds (well-known author, mother-in-law) and splits words at line ends.

En dash (–)

The width of a letter n. It shows ranges and connections: pages 10–24, 9 a.m.–5 p.m., the London–Paris train. No spaces around it in US style.

Em dash (—)

The width of a letter m. It marks a sharp break, an aside or an emphatic addition: The answer—if there is one—will surprise you. US style (Chicago) uses no spaces; AP and most British publishers use a spaced en dash instead ( – ).

Typing them

Mac: en dash = Option + hyphen, em dash = Option + Shift + hyphen. Windows: en dash = Alt + 0150, em dash = Alt + 0151 (numeric keypad). Word and Google Docs also convert two hyphens into a dash as you type.

Frequently asked

Is the em dash overused?

It can be. More than one or two pairs per paragraph makes writing feel breathless; commas, parentheses or a colon often work as well.

Should I put spaces around an em dash?

Chicago and most US books: no spaces. AP style: spaces. Pick one and be consistent.