How to use an en-dash and em-dash correctly? (BrE)
43 comments
·March 22, 2025account-5
StableAlkyne
> Recently I was accused of using AI to produce something because of my use of em-dash
Absolutely absurd of them to accuse you of using AI just because you used punctuation above a middle school level.
0_____0
AI reliably uses em-dash, normal people writing generally do not, even if they know what they are, because it's more complicated to insert them. So yeah, there's a reason it's known as a "tell."
StableAlkyne
I routinely use em-dashes in technical/scientific writing. The GP was talking about a false accusation in university — a place where you generally produce formal writing.
>it's more complicated to insert them
Word automatically replaces the hyphen with it when between words surround by space — because it's the correct punctuation. I sincerely hope you don't believe it's too complicated when the task is done for you by Word — the most popular word processor. Additionally — just to test it out — long pressing hyphen yields the character on my phone. This has allowed me to effortlessly pepper this reply with slightly extended — and a touch controversial — horizontal lines.
Just because your writing style doesn't use em dashes — a rule taught to literal school children — doesn't mean it's not "normal."
Finally, I am sorry to report that my use of the em-dash has not allowed me to transcend humanity and become a cyborg — though I will return with a follow up post if I suddenly sprout a Serial port.
K0balt
These days I just use a dash and it gets autocorrected into an em-dash. So I guess AI put tithe em-dash there, but it didn’t write my essay.
vincent-manis
My spelling is generally very good, and I know the difference between “e.g.” and “i.e.”. I guess I'm an AI.
account-5
I write in quarto markdown so en-dash is '--' and em-dash is '---' with is converted for me.
richardatlarge
chatGPT has a strange allergy to the semicolon— never uses them. that’s why it overuses and misuses the em-dash
acheron
iOS autocorrects -- to an em dash. It's not complicated at all.
perihelions
- "normal people writing generally do not"
You're generalizing inappropriately across cultural boundaries. Is the author of the OP article an abnormal human? Does "normal" mean "of average writing level"—is it now socially acceptable to ostracize and bully people who write well?
Because, when you're accusing people of being bots (like the HN parent related), that's a seriously unpleasant form of bullying. It's dehumanizing, quite literally. (When you write with sincerity, you pour your own humanity into your words; what does it mean to deny that?)
K0balt
Uuurgh. I’m a writer by trade and this has become a way for people who find my writing inconvenient to dismiss my thoughts.
I’m finding an impulse while writing these days to censor writing styles which are much more efficient at conveying complex thoughts in favor of styles which are more “human” but fail to convey nuance.
It’s debilitating to anything beyond discussion of sound-bite sized thoughtlets.
I fear that this will be a race to the bottom for human discourse and intellect.
airstrike
I suppose the trick is to use the uncorrected em dash--like this--so nobody thinks you're a cleanly formatted LLM.
More generally I guess the more punctuation mistakes you make, the lower the chances your text is flagged as written by AI, so there's now an optimal amount of mistakes that maximizes the perceived value of your work.
perihelions
I've seen people accusing each other on HN of being LLM's over the em-dash.
FumblingBear
The same thing has been happening to me lately too. Someone asked if I really knew and typed the alt-code every time I use it and I replied yes, if I'm on a Windows machine. On the one hand I agree it's often a tell for AI slop, but it's frustrating that nobody seems to dig any deeper than that anymore.
nayuki
Additionally:
* Use the minus sign /−/ (U+2212) when formatting numbers, because the default hyphen-minus /-/ (U+2D) just looks wrong: "It is −1 °C vs. -1 °C." Moreover, the correct minus has the same width as plus (− vs. +).
* Rare, but use the figure dash /‒/ (U+2012) or figure space / / (U+2007) if you need a placeholder character that is the same width as a single digit. For example, "Guess the PIN: 1‒34."
perihelions
On Linux you can use the Compose key[0] to type these without any friction. It's simply --- for the em-dash and --. for the en-.
Lammy
I can't live without this. I also use WinCompose on Windows and Karabiner Elements on Mac which I find vastly superior to the native special-character input methods of both:
benji-york
For the people that also use macOS: Option + hyphen and Shift + Option + hyphen.
pwdisswordfishz
Why bother when you have (Shift+)AltGr+hyphen, though.
kps
Many keyboards don't have AltGraph and many layouts use it poorly.
01HNNWZ0MV43FF
Next they're going to tell me that forward slashes and division signs are different
fsckboy
the article would be improved if they addressed the historical facts of typewriters, telegrams, teletypes, and ASCII instead of just presenting this view which is typesetting and unicode. (could also mention fixed pitch vs variable pitch/proportional spacing)
typing on a typewriter or computer keyboard (without fancy multi-key workarounds), you can't distinguish between a hyphen and an n-dash (not to mention the minus sign); you use the same hyphen key for all those, and represent an m-dash with two--hyphens. That's the starting place for most people who will read this article, and that should be the starting place for the article, if only to say "everything you thought you knew is wrong, here's how typesetting works..."
ghaff
And, to tell you the truth, while reliably using em-dashes in a word processor. I mostly just use hyphens on a mostly text site (or even an email) and don't bother with en-dashes at all. I guess I use em-dashes for formal/fancy stuff.
OptionOfT
There was a time where the man pages on Debian(derived) were being mangled by groff.
Groff made a change that when an author typed - (hypen-minus), it would be empitted as ‐ (hypen). In order to actually display a hypen-minus, it would need to be entered as \-.
We can argue about what is semantically the right way of displaying dashes, but because the majority of existing manpages don't properly escape the dash, this change broke searching in manpages.
You couldn't do /--location (search, hypen-minus, hypen-minus, ..., <enter>).
keane
Related: https://practicaltypography.com/hyphens-and-dashes.html
Butterick’s Practical Typography 2º Edition https://news.ycombinator.com/item?id=26688142
tlhunter
In vim insert mode you can type `Ctrl+k - m` or `Ctrl+k - n` to insert them.
I_complete_me
Slight correction: m-dash `Ctrl+k -M` or, for n-dash `Ctrl+k -N`.
What also works (though more cumbersome) are:
For m-dash: Ctrl+q u2014 and for n-dash: Ctrl+q u2013
My vim set up requires Ctrl+q but probably it's normally Ctrl+v, may need to check.
kps
Fun fact: Vim ^K sequences follow RFC1345, but nobody else does.
benji-york
As a long-time Vim user I am very happy to learn this trivia.
ycombinatrix
This is good to know! I knew Word converted "--" into a longer line but I did not know what it was.
I cannot wait to correct someone for using the wrong symbol. I am frothing at the mouth.
rahimnathwani
In Google Docs, single/double/triple minus signs are substituted thus:
single: unicode 45 (regular minus sign)
double: unicode 8211 (en dash)
triple: unicode 8212 (em dash)
7734128
I'm in general opposed to the entire concept.
One character is enough for all these use cases and having three, or more, separate characters is a bug not a feature.
blindstitch
You don't have to use them if you want, and I would never bother in some throwaway internet comment where context clues work well enough, but they serve an important purpose in typography that date back to the invention of the printing press or before. Each of these typographic marks signals uses that greatly differ syntactically and linguistically. In another sense, these are building blocks of design, which revolves around subtle yet explicit visual cues. Giving the reader those cues eliminates ambiguity by unambiguously establishing the writer's intent. That in turn promotes visual flow, which is essential when typesetting something hundreds of pages long. If you ever find yourself in this situation, you'll be happy they exist!
ghaff
As someone who does use em-dashes (and never en-dashes) I don't really disagree. Double quotes in particular are a ridiculously overloaded piece of punctuation. On the other hand em-dashes have some aesthetic appeal vs. hyphens or double hyphens as I would use on a site like this. (Even if I think there is legitimate debate over whether they should have spaces around them or not.) En-dashes? I was on the style committee at a prior company and I don't think we used them because it would have been another thing copyeditors had to fix every time.
sgarland
> Double quotes in particular are a ridiculously overloaded piece of punctuation.
Pythonistas everywhere: how dare you.
chasil
I actually learned this in a book for Xerox Ventura Publisher in the late '80s.
albert_e
I don't have a great writing style -- it's too verbose and often has run-on sentences that seemingly never end.
And I do use the en-dash / em-dash a lot -- probably incorrectly.
All flaws aside, it would be very unfair of anyone -- much less any purported expert in AI -- to suggest that frequent usage of this punctuation -- irrespective of whether it is tasteful or not -- is a sign of AI generated text (or slop).
The en and em dashes and my 3rd and 2nd favourite punctuation marks after the semi-colon.
Recently I was accused of using AI to produce something because of my use of em-dash. I was able to show my use of the character going back years in my university work, long before recent AI.