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.
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."
"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
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
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.
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.
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
'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 dash', University of Sussex, 2013
'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.