A relatively modern dictionary (I don’t know which one, because we’ve cut out the pages and used them as wallpaper in our bathroom, but I know it’s less than 20 years old) indicates that R’s is one correct pluralization of R, as is Rs, but whichever dictionary this is, it’s kind of a no-name brand, so I’m not sure I trust it.

I’ve always wondered what the best way was to pluralize single letters or numerals, like 2’s or 2s. What’s correct?


2 Answers 2


From this Wikipedia page:

  • It is generally acceptable to use apostrophes to show plurals of single lower-case letters, such as be sure to dot your i's and cross your t's. Some style guides would prefer to use a change of font: dot your is and cross your ts. Upper case letters need no apostrophe (I got three As in my exams) except when there is a risk of misreading, such as at the start of a sentence: A's are the highest marks achievable in these exams.
  • For groups of years, the apostrophe at the end cannot be regarded as necessary, since there is no possibility of misreading. For this reason, most authorities prefer 1960s to 1960's (although the latter is noted by at least one source as acceptable in American usage), and 90s or '90s to 90's or '90's.
  • The apostrophe is sometimes used in forming the plural of numbers (for example, 1000's of years); however, as with groups of years, it is unnecessary: there is no possibility of misreading. Most sources are against this usage.
  • The apostrophe is often used in plurals of symbols. Again, since there can be no misreading, this is often regarded as incorrect. That page has too many &s and #s on it.
  • Finally, a few sources accept its use in an alternative spelling of the plurals of a very few short words, such as do, ex, yes, no, which become do's, ex's, etc. In each case, dos, exes, yeses (or yesses) and noes would be preferred by most authorities. Nevertheless, many writers are still inclined to use such an apostrophe when the word is thought to look awkward or unusual without one.
  • 4
    heh funny, to me "1960's" makes much more sense. i think I interpret it as "the times of 1960" or "1960's", like a possessive. also "nos" and "dos" just looks strange. "no's" and "do's" much better IMO.
    – Claudiu
    Commented Nov 18, 2010 at 16:17
  • With regard to the last point, what would be the correct plural if one wished to use quotes to delineate the thing being made plural (e.g. did his speech contain seven "You know"s, or seven "You know"'s)? The latter seems much better visually, since having a quotation mark with letters on either side looks very odd, but I'm not sure which is orthographically preferable if one can't use typography as an indicator.
    – supercat
    Commented Oct 15, 2012 at 22:40
  • @Claudiu: I agree with you about the 1960's. Among other things, the 1960's consisted of 1960, 1961, 1962, etc. and not just repetitions of 1960. I'm perhaps more inclined to use apostrophes than some pedants, because believe the most important rule should be that that when a mark makes things easier to read, its use is likely appropriate, regardless of what any "rules" say. I would suggest that an apostrophe is often appropriate to separate text which should be read with different levels of "indirection". For example, I would pluralize "ATM" as "ATM's", since such usage helps make clear...
    – supercat
    Commented Oct 15, 2012 at 23:11
  • ...that the things to the left of the apostrophe should be read differently from those to the right. I would regard such usage as being similar conceptually to the hyphen in the verb "re-cover" meaning "to cover again", except that a hyphen would generally imply a syllable break, but the "read as letters" and "read conventionally" parts of "ATM's" and "DQ'ed" should not have a syllable break between them.
    – supercat
    Commented Oct 15, 2012 at 23:14
  • Another area where apostrophe-s may do a better job of signaling a plural form than s by itself is in product names that have inventory-number-like model names. For example, the plural form of the Apple iPhone 5s is arguably clearer as iPhone 5s's than as iPhone 5ss.
    – Sven Yargs
    Commented Aug 3, 2016 at 17:38

You could use a hair space (U+200A in Unicode) instead of an apostrophe. For example:

With apostrophe
The do’s and don’t’s of the 1960’s. Be sure to dot your i’s and cross your t’s. 22 has two 2’s.

With no extra space
The dos and don'ts of the 1960s. Be sure to dot your is and cross your ts. 22 has two 2s.

With hair space
The do s and don't s of the 1960 s. Be sure to dot your i s and cross your t s. 22 has two 2 s.

With hair space and italics
The do s and don't s of the 1960 s. Be sure to dot your i s and cross your t s. 22 has two 2 s.

  • 6
    I like the hairspace with the number, and the italics for the pluralized words, but quality typography is not available in all contexts where one uses text.
    – supercat
    Commented Oct 15, 2012 at 22:35
  • You're talking about typesetting, not written language. But if we were discussing the four typeset options you list, I'd still pick the apostrophe, since it's the easiest comprehended.
    – Xalorous
    Commented Aug 25, 2016 at 0:10

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.