These three punctuation marks all look very similar, and yet they cannot be used interchangeably. They only differ in length on writing and it is important to go for a correct one, depending on what exactly you want to say in your sentence. But how are the hyphen and the en dash different from the em dash?

The Hyphen

The hyphen (-) is shorter than both the em dash and the en dash. Its two main uses are for compound words and for numbers that aren’t inclusive. For instance, words, such as self-esteem, or client-centered, all need a hyphen. Similarly, social security numbers are separated by hyphens as well.

The En Dash

The en dash (–) is slightly longer than the hyphen but still shorter than an em dash, and it also has its own functions. Firstly, you need to use an en dash if you want to indicate a range of numbers or a span of time or distance. In these cases, it has the meaning of “through” or “to”.

For example, a teacher might assign her students to read pages 50–84 from the textbook as a part of their homework. Or, if you own a business, you could say that the 2017–2018 fiscal year was your most profitable year so far. Finally, you could say that the China–France flight is a very long one. All of these sentences require an en dash.

Secondly, you need to use an en dash if you want to show a connection between two terms. They are used for phrases that already have a hyphen, and in those instances where your modifier consists of two or more words.