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Part of: Grammar points

Hyphens and dashes

Last updated: 30 January, 2020

Following this helps people with:

  • time pressures: words need to make sense immediately

  • multi-tasking: when attention's divided unclear words puzzle

  • cognitive impairments: clear words take less mental effort

  • visual impairments: text to speech software may read them out


Use hyphens and dashes sparingly. They can cause readability issues.

1. Only use a hyphen if the word is confusing without it.

2. Do not use hyphens for time and date ranges, instead use "to".

3. Make sure your hyphen usage is up to date.

4. Be consistent with your hyphen choices.

5. Avoid using dashes whenever possible.

6. If you do use a dash, use an en-dash, not a hyphen or an em-dash.

Usability evidence

1. Only use a hyphen if the word is confusing without it.

Hyphens slow online comprehension as words with hyphens take longer to scan. They can make the reader need to stop to unpick meaning.

The argument for hyphens is that they avoid ambiguity. But with a little thinking, you can usually rewrite something clearly and simply without needing a hyphen. 


"This cereal is sugar-free." – with hyphen

"This cereal has no sugar." – without hyphen


"250-year-old trees" – with hyphens

"250 year old trees" – no hyphens, meaning ambiguous 

"Trees that are 250 years old" – no hyphens, meaning clear

Sometimes you do need a hyphen for clarity, where a word has a different meaning without the hyphen, like re-cover and recover or co-op and coop. 


"They recovered the sofa." – no hyphen, meaning ambiguous

"They re-covered the sofa." – hyphen, meaning clear

With the first sentence, did they get it back from a debt collector, did they make it well again or did they put a new cover on it?

Of course, you could just write "They put a new cover on the sofa."

2. Do not use hyphens for time and date ranges, instead use "to".

"To" is easier to scan on a page, and text to speech software will read it out as "to". Rather than reading out "en dash", "dash", "hyphen" or even "minus".


10am to 11am not 10am-11am

1 to 4 February not 1-4 February

2020 to 2024 not 2020-2024

3. Make sure your hyphen usage is up to date.

Hyphens often disappear if a compound word becomes widely used. Check what's most commonly used today. 


Inter-networking became inter-net became internet 

Coffee-maker became coffeemaker

Brides-maid became bridesmaid

Hyphen use in prefixes can also declines. 


De-regulate became deregulate

4. Be consistent with your hyphen choices.

Do not alternate using and not using a hyphen for a particular word.

Follow the same rules about hyphens across your online channels and offline content. Consistency in a document and organisation is more important than being 'correct' just in the bit you're editing.


If you choose to write "full-time" then use that throughout your content.

You may confuse your user if you then write "fulltime". Or they'll lose confidence in you because it looks like you cannot decide. If it's a job ad and they need to mention the working pattern in their application, it could be a real problem. They may well want to use what you've used.

5. Avoid using dashes whenever possible.

Replace dashes with commas if you can. Commas are treated very naturally by text to speech software by default. That is, they are not read out.

Many screen reading applications will read out "en dash" for every "–". Yes users can calibrate tools they use, but why should they, and what if they do not know how to?

We want to carry out punctuation and screen readers usability research.

6. If you do use a dash, use an en-dash, not a hyphen or an em-dash.

The en-dash is:

  • wider than a hyphen, narrower than an em-dash, same length as letter ‘n’

  • sometimes used the way brackets or commas are

  • used with a space before and after it

The em-dash is:

  • wider than the hyphen and en-dash, same length as letter ‘m’

  • used in US English in place of en-dash, without spaces around it

  • very unusual in UK English

Usability evidence

'Does hyphenation increase readability?', 2012

'Why Don’t Screen Readers Always Read What’s on the Screen? Part 1: Punctuation and Typographic Symbols', Paul Bohman, Deque, 2014

'Hyphen', Oxford Living Dictionaries, 2010

'The hyphen' University of Sussex, 2013

'The Trouble With EM ’n EN (and Other Shady Characters)', 2001

'The dash', University of Sussex, 2013

'Hyphens or en dashes—which are more readable when used in number ranges?', 2014

'Perilous Punctuation: Use the Dash With Panache', 2015

'Em dash', Oxford Living Dictionaries, 2018

'Typography and language in everyday life: prescriptions and practices', Walker, S., Harlow: Pearson Education, 2001. Book.

'The new Oxford style manual', Oxford University Press, 2016. Book.

'Communicating in style', Joshi, Y., TERI, The Energy and Resources Institute. 2003. Book.

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