What is today’s date? If you answered this question with February 22, 2025 (read February the twenty-second, two thousand and twenty-five), you should go on reading.
The day-month-year date format (e.g., 22 February 2025) is officially adopted by the vast majority of the world’s countries.
The year-month-day date format (e.g., 2025-02-22) is officially adopted by China, Japan, Korea, and Iran, and is also the date format of the ISO 8601 standard.
The month-day-year date format (e.g., February 22, 2025) is officially adopted by the USA only (although contamination of this format can be found in a few other countries). Like most standards adopted in the USA, the month-day-year date format is bizarre at best, as shown in the following illustration:
Yet, nowadays…
The month-day-year format is used by a large number of people speaking English as a foreign language, who adopt Americanisms like these without thinking them through. Unfortunately, this is the case even in Europe, despite the fact that every European country–including the UK–officially adopts the day-month-year format.
Long story short: if you live outside the USA but use the month-day-year format when writing or speaking in English, you are doing it wrong. You do not suddenly use miles, pounds, and Fahrenheit when writing or speaking in English, right? Then please, in the interest of logic, do not use the month-day-year date format either. 🙂 Keep using the day-month-year or year-month-day date formats, like you learned in school. If you want to avoid any misunderstanding, just use the variants d MMMM yyyy or d MMM yyyy of the day-month-year date format (e.g., 22 February 2025 or 22 Feb 2025), which are the most readable ones.
So, once again, what is today’s date? It is 22 February 2025 (read the twenty-second of February two thousand and twenty-five).
28 November 2024 at 16:43
The diagram indicates a lack of understanding of the US format. The right hand part should take the month-day partial pyramid from the middle part, and the year from the left. The reasoning (and why it stays in use) is that month-day follows the same place value convention we do with numbers: largest-to-smallest, but leaves the year to last so that it may easily be admitted, as it often is due to context. The European format allows for year omission but sacrifices conventional place value to accomodate this without dissonance. The international format follows place value and avoids dissonance but disallows omitting the year.
So we have three formats that each satisfies one or more priorities but none achieves all of them. There’s no logical basis for saying one is superior or inferior to the others, just better or worse depending on the distribution of uses.
29 November 2024 at 08:26
Ugh, year to last so it can be “omitted” not “admitted”, hopefully it was clear what was meant. 🙂
2 April 2021 at 19:31
Month/Day/Year is better by far. You can store dates in the correct order extremely easily by just sorting alphabetically. For instance, if you have a ton of files each labeled by their date in D/M/Y, you get listed ‘1st of January, 1st of February, 1st of March’, but if you have it labeled in M/D/Y, you get ‘1st of January, 2nd of January, 3rd of January’. A far easier way to get to the result you want
24 April 2021 at 13:31
Oh really? Using the month-day-year date format in file names and sorting files alphabetically leads to seeing first all January dates for all years (e.g., 2001–2021), then all February dates for all years, and so forth. It does not seem helpful to me, does it? If you want a one-to-one mapping between sorting alphabetically and sorting by date, you need to use the year-month-day date format in file names, as recommended by the ISO 8601 standard. So no, the month-day-year date format is not better by far—it is, in fact, inferior. Feel free to use it in the US, but please do not bother the rest of the world.
23 January 2025 at 23:05
I would suggest that the file storage argument in general is unimportant, as organization is up to the individual in many cases. Anyone who organizes their files in folders by year (say, a 2024 folder) would be fine with mm-dd-yy or yy-mm-dd while people who leave their files in a conglomerate without any organizing folders would benefit only from the yy-mm-dd format. With proper organization of folders, any date system is valid and thus mm-dd-yy is not “inferior” by this standard.
I totally agree that the mm-dd-yy format is outdated, and I do feel that it would be more beneficial for clarity reasons that the US should adopt the yy-mm-dd / dd-mm-yy, but calling ‘Americanism’ that seep into British English ‘contamination’ seems a bit much mate. Great argument for dd-mm-yy / yy-mm-dd, but this post and your comments come across less as a genuine academic argument and more as a bitter display of distaste towards ‘Americanisms’ (especially with the closing “do not bother the rest of the world” of your comment). Global English is very much shaped by all its speakers and not just British English, though I agree that the dates should be standardized.
5 July 2020 at 06:11
Do-Re-Mi is lost, and started to sing: Re-Mi-Do!
3 May 2017 at 17:41
Un grande classico 😉 https://xkcd.com/1179/
4 May 2017 at 20:23
Nice one
9 March 2017 at 23:01
Er.. All speeds & distances on UK road signs are in miles.
18 August 2016 at 04:03
Well at least for this “stop the American contamination” post you only exhort people to stick to their local standard, rather than rally everyone to tweet their politicians and demand an immediate end to this “corruption.” In any case, as a software engineer, you should know that dates are (with few exceptions requiring extreme precision) best stored as Unix Epoch, and then converted into whatever the hell the user wants to see. Dates, timezones, summer time (aka daylight savings), non-Gregorian calendars, etc etc—it’s a nightmare best left to someone sick enough to figure it all out and program it into a nice library for the UI guys to use.
26 August 2016 at 22:11
This post has nothing to do with how dates are stored by a computer.
27 August 2016 at 05:47
Well, so you are talking about how students write dates on their papers? The vast majority of communication is now done through computers, including printed pages, which start out as electronic documents. Formatting the date to the local standard could be then a software solution. You say you’re a software engineer, so I’m just suggesting thinking like one.
27 August 2016 at 15:00
This post is about how dates are represented, with or without a computer. Yes, the vast majority of communication is done through computers, yet dates are typed manually and not reformatted automatically in most cases. Just think about short messages or emails, for example.
1 May 2015 at 11:49
Yes. many customs in the USA are different. I agree that our numerical dates can cause confusion in a foreign place. But to urge that we now change is a little like exhorting that we start speaking a more common language because there would be less confusion in foreign places (only a little like). Perhaps it is the inconsistency you wish to root out. Then you may wish to exhort that we start using good-gooder-goodest, just one example. I am not against a change to our date format. It would be good. What wouldn’t be good is for those who read your blog to start following your advice. Then you have bred confusion domestically. I believe we’d all have to make the switch. Do you have a plan, or are you just writing an essay?
10 May 2015 at 18:27
I am not trying to convince Americans to use the day-month-year format. This would be a lost cause. On the contrary, I am trying to convince anyone else in the world not to use the month-day-year format. In fact, I explicitly wrote “if you live outside the USA, but use the month-day-year format when writing or speaking in English, you are doing it wrong” in my article. As a European, I find it ridiculous that Europeans contaminate English with Americanisms like these, especially considering that every European country, including the UK, adopts the day-month-year format.
4 December 2013 at 12:00
The main problem is that… people never listen to common sense 😉
21 November 2013 at 11:12
I usually use Day-Month-Year, but sometimes it is really useful to write the date down the oposite way, year-month-day. Everyone who uses computers with “sort by date” know what I mean. Try sorting documents with the dates 21-11-2013, 29-11-2013 and 06-12-2013 it gets switched around because 06 is before 21 and 29. 2013-11-21, 2013-11-29 and 2013-12-06 will come out in the right order and easier to read which is much better for a good forlder structure.
22 November 2013 at 16:29
I agree with you Morten. The day-month-year and year-month-day date formats are complementary. I use day-month-year most of the time, since it is the most readable, but I use year-month-day in file names, since, as you pointed out, it guarantees that sorting by date corresponds to sorting by name.