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Almost everywhere I see the so called hyphen-minus (Unicode character U+002D and HTML symbol &#45) used as a minus sign, which is actually the standard hyphen character (Unicode character U+2010 and HTML symbol ‐) as you can see in this example equation:

hyphen(-minus) example as minus sign

As you can realize, in most fonts the hyphen-minus does not have the optimal width, thickness or position to represent a minus sign and therefore practicaltypography.com suggests to

use an en dash, which makes an acceptable minus sign in spread­sheets or mathematical expressions.

which looks like this when we follow our example:

en dash example as minus sign

But in my opinion this is a little bit misleading, because an en dash is also used to indicate spans or differentiation:

en dash span example

On the other hand there exists a “correct” minus sign (Unicode character U+2212 and HTML symbol −) for "everyday speech" but which is rarely used for some reason:

minus sign used in equation

I wonder now if a hyphen(-minus) sign, en dash or a minus sign should be used to represent a minus in typographic context.


As @PieBie and @Zach Saucier pointed out there are many use cases out there. But does the type of publication make any difference?

I mean why should we not use the same minus character when writing a mathematical equation or indicate a negative vote for a post for instance on this site:

example for minus signs: hyphen(-minus), en dash and minus sign


As a side note: I also dont know why no minus sign (U+2212) but rather a hyphen(-minus) gets displayed when we press the minus key - on our numpad. Why are there two same keys for different characters?

Note: The sans-serif typeface Arial was used in the examples.

  • "I wonder now if it is ok to be lazy and use a hyphen(-minus) sign or an en dash as minus" - this is completely opinion based as far as I can tell. Can you please try to rephrase this to make it less opinion based? – Zach Saucier Mar 17 '16 at 15:55
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    Additionally, could you provide more information on the type of publication? Is it a mathematical treatise where the minus sign is going to be used a lot, or is it a promotional flyer where the minus is used to indicate a discount? – PieBie Mar 17 '16 at 15:59
  • @PieBie: Should this really make a difference? :) – elegent Mar 17 '16 at 16:05
  • So you have no real use case in mind, you're just asking for the sake of asking? – Zach Saucier Mar 17 '16 at 16:08
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    You definitely should not use an an dash, because 5–10 reads “5 to 10” not “5 minus 10.” – Simon White Mar 18 '16 at 4:18
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If you want a minus sign, use a minus sign.

That's what it's for, after all.

That being said—unless you are writing for a mathematical publication or in a similar context it probably won't go noticed if you do use a hyphen or dash. I know I have used a hyphen-minus or en-dash countless times in the past.

As you mentioned in your question, there is no key for a minus sign on a keyboard, only a hyphen. For that reason alone, average Joe doesn't use a minus sign, he uses a hyphen (or hyphen-minus).

A few things to note.

A hyphen or dash will usually have a different vertical alignment to the minus and other mathematical symbols. It often isn't much but if you are using more mathematical symbols than just a minus sign it may be noticeable. If you are going to the trouble of using other correct mathematical symbols then it's not much more effort to use the correct minus sign.

A few examples of dashes and mathematical symbols in different fonts, to illustrate the difference in alignment:

enter image description here

If no minus sign is available, the en-dash should be closest in design and should be used instead.

Keyboard hyphen key

The hyphen key on your keyboard is actually called hyphen-minus because it is intended to be used as the minus sign and for hyphens/dashes. This character is still present in Unicode for compatibility reasons (its character code is U+002D), but Unicode also encodes the hyphen (‐, U+2010) and minus sign (−, U+2212) separately.

I assume no minus sign, or any specific dashes are included in keyboard layouts for a number of reasons. Firstly historical—it saved space on typewriter and early computer keyboard keys. Secondly, it wouldn't really make sense—how would you differentiate the various dashes, hyphen and minus sign? The length would be hardly noticeable in isolation and adding en, em etc would probably confuse anyone not versed in typographical terms.

With regards to your note on the numpad, I'm not sure why a minus sign isn't used. It seems like it should be. It may be for technical reasons. I'm not familiar with the engineering of a keyboard but maybe both hyphen(-minus) keys use (or historically did) the same circuitry. It may also simply be not to cause confusion, with two identical looking keys outputting different characters.

In short—If you are writing mathemtical formulae, use the correct symbol. Otherwise you can probably get away with a hyphen-minus or an en-dash (but if you're going to the trouble of using an en-dash, just use a minus sign!).


Some Related Reading

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    Fun fact: recently this caused a massive row on Meta Stack Overflow. Spoiler Alert: negative votes on the entire Stack Exchange sites are not indicated by a proper minus. (I did not notice until this was pointed out. Now it bugs me immensely 😀) – usr2564301 Mar 17 '16 at 19:02
  • That discussion is highly entertaining! I completely agree it should be a minus sign and I would much prefer if it was, but I'm not surprised at all—I'm more surprised when I do see a proper minus sign in any web design, or anything digital that isn't design/typography/academic related for that matter. – Cai Mar 17 '16 at 19:10
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    People do not agree on this point. Full Stop. When I suggested that one should use roman numerals because of the semantics not all people agree. Basically its a mess everybody uses hypen as minus everywhere even code that has a lot of expression uses the wrong character. There is not a easy way out of this question. Purist would like to use you know a actual minus but the pragmatics can not concede because it would mean a ton of documents to fix. – joojaa Mar 18 '16 at 19:32
  • I agree. It is a mess and there isn't really a way out of the issue. The roman numerals is basically the same argument. – Cai Mar 18 '16 at 21:11
  • Cursed be the person who made the design of hyphenminus on the keyboard. Why oh why, can not the operators on the numeric keypad give proper mathematical symbols. – joojaa Jul 4 '16 at 21:34

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