You may or may not believe it, but sometimes even co-workers here at Typeright struggle to find out when to use a hyphen in English. Then I’ll get the question ‘To hyphenate or not to hyphenate?’ and that’s when we figured we should create an own article for that specific topic. Yes, this one’s for you, Christoph.

What is a Hyphen?

This beautiful straight line here “-” is called a “hyphen.” You may have also heard the name “dash.” However, even if they look the same or similar (meaning that a dashed line is sometimes noticeably longer than the line of a hyphen), their usage is very different. But we’ll get there later. 

The hyphen’s primary purpose is to join words and signal the reader that those two (or more) elements are linked together to better understand a sentence’s meaning and provide clarity. But hyphens can also act as a separator for long words that may not make the cut as a whole when starting a new line in a document or piece of text. 

And then there’s another critical thing that needs mentioning: style and preferences. Several English nouns consist of two or more words, and it’s not uncommon that there are hyphenated and non-hyphenated versions circulating. “Makeup Tutorials” and “Make-Up Tutorials” are grammatically both correct and do mean the same thing. When it comes to hyphens, the many English dictionaries around the globe (independent of American or British English, by the way) prefer different “hyphenating styles.” So sometimes there’s no right or wrong, as long as you stick to one of the styles throughout your whole piece of writing. 

“Gimme Some Rules!”

It’s true – (<– this is a “dash,” by the way) the usage of hyphens are sometimes based on a specific style. However, there are indeed general rules you always have to follow when using hyphens.

1) Compound Adjectives

For two or more words that act as a single description or idea, you use a hyphen to combine them and create a compound adjective. They typically stand before a noun and hence modify it or give it a specific meaning. 

I live in an off-campus apartment.
This is a well-known fact.
A middle-aged woman stood outside my house.
The friendly-looking dog licked my hand.

However, if the compound adjective stands after the noun, the hyphen is not necessary.

I live in an apartment off campus.
This fact is well known.
Outside my house stood a woman of middle age.
The dog licked my hand and looked friendly.

2) Unusual Compound Words

Especially in creative, vivid, and original writing, some people tend to create new compound nouns and adjectives. 

Creative Compound Nouns:

I changed my diet and became a plant-food enthusiast.
The dress had a bell-like shape.
The steak had a chewing-gum-like consistency and texture.

Creative Compound Adjectives:

The place where I grew up had a little-town charm.
The suspicious-looking neighbor eyed him through his spectacles.
The sun-burned-looking guy at the bar enjoyed his Piña Colada.

3) Already Established Compound Words

There are compound words that are already well established with hyphens so that you use them naturally. 

state-of-the-art
up-to-date
mother-in-law
ex-husband
get-together (= party)

4) Age

If you don’t use numbers to tell someone’s or something’s age, but write it out as words, then you need hyphens. The timeframe itself (years, days, or any other period of time) doesn’t matter.

We have a three-month-old baby.
The middle-aged man is dancing on his own.
This three-centuries-old bracelet is worth millions.

4) Numbers

If you write out all the numbers from 21 (twenty-one) through 99 (ninety-nine), you need hyphens.

thirty-four / 34
sixty-five / 65
eighty-two / 82

5) Prefixes with Proper Nouns and Adjectives

Words that consist of prefixes like “a, un, de, ab, sub, post, anti, etc.” and proper nouns or adjectives should be hyphenated as well. 

I had my last dentist appointment around mid-July.
He saw his ex-wife last weekend at a friend’s party.
She asked her all-knowing brother for advice.
They had to re-do their assignment.
Some co-workers don’t know how to use hyphens.

6) Line Breaks

Words that won’t fit into the same text line anymore but leave too much space when moved as a whole to a new line below can be “broken down” with a hyphen. Just be careful that you separate the word per syllable and not just randomly between the letters. 

We hired a new graphic-
designer to help us.

For our wedding, I looked for photo-
graphers that had the best reviews.

She handled the case with the utmost dis-
creation until we finished the business.

What’s The Deal With Dashes?

Depending on the font or format, dashes look either the same or highly similar to hyphens, albeit we use them for entirely different things. 

In general, dashes are used to separate parts of a sentence and create emphasis on them. They often work the same way as brackets do, like adding parenthetical statements or comments. If we’d go into more detail here – which we won’t (but will in another article) – we’d tell you that there are precisely four types of dashes: the “en dash,” “em dash,” “2em dash,” and the “3em dash.” So, for now, it’s essential to know that we distinguish between spaced (with a single space before and after it) and unspaced (no space before and after it) dashes.

Spaced Dashes

Creating emphasis on a statement:

She might do something entirely different – you’ll never know.
You think I’m lying – I’m not.
He may come to the party – we’ll see.

Comments that interrupt a sentence: (mostly direct speech)

“Please open your books – stop chatting David – at page 82.”
“Follow me please – watch out for the stairs here – and have a seat.”
“This path leads – ouch! Watch out for the roots on the ground – directly to the lodge on the hill.”

Adding extra information:

I was awed by the number of books – old classics and unwrapped new releases – and couldn’t wait to lay my fingers on them.

When the shelf broke down, everything on it – historic clay sculptures and valuable teacups – smashed to the floor.

“I think we’ve covered everything from the grocery list – honey, butter, noodles, olive oil – and should head to the checkout now.”

Unspaced Dashes

Indicating ranges:

I attended high school between 1981-1985.
Pablo Ruiz Picasso (1881-1973) was a famous painter and sculptor.
There were 20-25 students in the classroom. 

Illustrating or contrasting the relationship between two things or values:

I write a book about a father-son relationship.
The local baseball team beat their opponents 9-7.
They updated the United States–Canada free trade pact recently.

Indicating unfinished or interrupted sentences:

“And that’s when–” she said, unable to finish the sentence due to a fit of laughter.

He mumbled: “I never thought he was capable of–” “It’s ok, I understand,” she said. 

“I’m wondering when they’ll arr–” he stopped midsentence when he saw them already waiting on the porch outside.

Departure and destination (as seen on train or airport terminals):

The train Boston-New York leaves in an hour.
I’ll take the flight London-Edinburgh tomorrow.
They’ve immensely improved the train route Vienna-Rome.