I just use millis since epoch
(Recently learned that this isn’t accurate because it disguises leap seconds. The standard was fucked from the start)
This is the way.
How is day smaller than month? There are up to 12 values for month, but up to 31 for days
obvious troll is obvious
It’s sorted by the length of time, so a day is shorter than a month.
I use ss/mm/hh/dd/MM/YYYY
t.european
Hot take: 2025-Jan-27 is better than 2025-01-27 in monolingual contexts.
The beautiful part of 2025/01/27 is that it can inherently be sorted without formatting.
finally a correct version of this diagram
i never saw year first in Europe.
You’re reading the post backwards.
This pyramid visualisation doesn’t work for me, unless you read time starting with seconds.
2024-01-26-11-40-20
I get it, just pyramids are misleading, also year-month-day is better because resulting number always grows. 😺
A bit out of context, but is your username and instance a reference to nescafe?
Not really but now that you mentioned it, it will! 😄
That’s an interesting coincidence
2025-01-26T11:40:20, you mean?
Hold on there pal that time zone is ambiguous. Did you mean 11:40:20 UTC? If so, don’t forget your Z!
Yeah
A pyramid is built bottom to top, not top to bottom. That’s also one of the strengths of the ISO format. You can add/remove layers for arbitrary granularity and still have a valid date.
Yeah, but people read top to bottom. The best way to do it would be to have upside down pyramids. With the biggest blocks at the top representing the biggest unit of time (YYYY) and the smallest blocks at the bottom representing seconds & smaller.
What do you think this is some sort of pyramid scheme?
Offene Feldschlacht betritt den Raum
This is Belize and Micronesia erasure.
DD-MMM-YYYY master race
Don’t you mean: “Right there! Stop you, I’m going to.”
Yoda-ass date structure.
What day, of what month, of what year is it? It’s ordered by importance dammit!
25th of July, 2024 is confusing?
There’s no ambiguity with the format, since it’s impossible to mix up month and day
No. But 2024, the 25th of July is clumsy both spoken and written.
July 25th, 2024 is okay but gives off middle child vibes.
25th of July, 2024 is ordered small to big, rolls off the tongue and when written nicely seperates both sets of numbers for ease of readability.
The only other alternative I will accept is Julian dates. Today is Day 26 of 2025.
July 25th, 2024 is okay but gives off middle child vibes.
The fuck does that even mean? This is literally how people speak dates out loud.
yes, when the month is written non-numerically (and the year is written with four digits) there is no ambiguity.
but, the three formats in OP’s post are all about writing things numerically.
In some contexts, writing out the full month name can be clearer (at least for speakers of the language you’re writing in), but it takes more (and a variable amount of) space and the strings cannot be sorted without first parsing them into date objects.
Anywhere you want or need to write a date numerically, ISO-8601 is obviously much better and should always be used (except in the many cases where the stupid formats are required by custom or law).
…looks more like i’m you, gonna right, stop there…
I don’t know why anyone would ever argue against this. Least precise to most precise. Like every other number we use.
(I don’t know if this is true for EVERY numerical measure, but I’m sure someone will let me know of one that doesn’t)
They are all equally prescise. American one is stupid just like their stupid ass imperial units. European one is two systems slapped together(since they are rarely used together and when they are its the iso format) and iso is what european standard should be.
You misunderstand my comment.
I’m saying the digits in a date should be printed in an order dictated by which units give the most precision.
A year is the least precise, a month is the next least, followed by day, hour, minute, second, millisecond.
You are looking not for precision but for largest to smallest, descending order. this is distinct from precision, a measure of how finely measured something is. 2025.07397 is actually more precise than 2025/01/27, but is measured by the largest increment.
And to address the argument on precision versus descending. I disagree. An instrument counting seconds is more precise than a machine counting minutes, hours, days, weeks, months etc… And that holds true through the chain. The precision is in the unit.
We can debate this all day. And I can’t honestly say that I would take either side in a purely semantics argument.
But the wording comes directly from RFC3339 which is, to me, the definitive source for useful date representation.
https://www.ietf.org/rfc/rfc3339.txt
5.1. Ordering
If date and time components are ordered from least precise to most precise, then a useful property is achieved. Assuming that the time zones of the dates and times are the same (e.g., all in UTC), expressed using the same string (e.g., all “Z” or all “+00:00”), and all times have the same number of fractional second digits, then the date and time strings may be sorted as strings (e.g., using the strcmp() function in C) and a time-ordered sequence will result.
Largest to smallest is also wrong. In 2025/01/28, the 28 is larger than the 01.
It should be “most significant” to “least significant”
largest to smallest is correct. 1 mile is larger than 20 meters. if i had specified numerical value or somesuch, maybe you’d be correct. though significance works as well.
Largest to smallest is at best ambiguous. It can refer to the size of the number itself, or the size of the unit.
There is a reason this exact concept in maths/computer science is known as the “significance” of the digit. Eg. The “least significant bit” in binary is the last one.
Sorting with either the month or the day ahead of the year results in more immediately relevant identifiable information being displayed first. The year doesn’t change very often, so it’s not something you necessarily need to scan past for every entry. The hour changes so frequently as to be irrelevant in many cases. Both the month and the day represent a more useful range of time that you might want to see immediately.
Personally, I find the month first to be more practical because it tells you how relatively recent something is on a scale that actually lasts a while. Going day first means if you’ve got files sorted this way you’re going to have days of the month listed more prominently than months themselves, so the first of January through the first of December will all be closer together then the first and second of January in your list. Impractical.
Year first makes sense if you’re keeping a list around for multiple years, but the application there is less useful in the short term. It’s probably simpler to just have individual folders for years and then also tack it on after days to make sure it’s not missing.
Also, like, this format is how physical calendars work assuming you don’t have a whole stack of them sitting in front of you.
By keeping years in different folders you are just implicitly creating the ISO format: eg.
2025/"04/28.xls"
Maybe in programming or technical documentation, but no, when I check the date I want to know the day and the month, beyond that, it’s all unnecessary information for everyday use, and we have it right in Europe.
You can’t change my mind. ¯\_(ツ)_/¯
You can’t change my mind.
That’s not a good thing. That attitude limits you from improving how you do things because you’ve gotten emotionally attached to some arbitrary … never mind. Have a nice day.
These people are just too far into the ISO rabbit hole. I completely agree with you that DD.MM.YYYY is the best format for everyday use.
Nah. Sort that alphabetically and you end up with a useless list.
And sorting the other formats alphabetically does not yield the same result?
No…?
Thank you! 😂
the “best” format for everyday use is each individual person’s personal preference.
you may be more used to DDMMYYYY due to culture, language, upbringing, and usage. in the same vein, i am more used to YYYYMMDD because in chinese we go 年月日 (year-month-day), and it makes organizing files and spreadsheet entries much more intuitive anyways.
Well in that case people should stop complaining about us wanting to use DD.MM.YYYY it’s perfectly fine and the only format that should be shot on sight is MM.DD.YYYY
You can do 1-26, skipping the year and adhering to ISO 8601.
You can do 1-26
I don’t know what this means, also I don’t have to adhere to anything, the European format works perfectly well for me, so… ¯\_(ツ)_/¯
1-26 or 01/26 is a way of writing the month and day. in this particular example, it is describing the 26th day of January, or January 26. the year is omitted in this instance because, in this context, it is a way of demonstrating how a month and day can still be conveyed in order of significance without fully adhering to ISO 8601 guidelines.
So it’s just adding the American format (which categorically does not demonstrate how a month and day can still be conveyed in order of significance, but literally the opposite) in to the mix and not providing any help or making things any simpler lol
Thanks for explaining, but if the person who introduced the 1-26 concept in to the conversation (and could have easily just said “MM/DD” to make their point significantly clearer), or the other person with their lecture are actually trying to change my, or anyone else’s mind, or make their personal preference more appealing to others, this (making things more complicated, when they are already perfectly straightforward, just not how they like it) isn’t the fucking way to do it lmmfao
2025-01-26 so it’s 26.01. It’s easy to look up. All you need to know is that the date goes YYY-MM-DD (year -> month -> day). You do the same thing when you write 26.01 instead of 26.01.2025, since you are just dropping information about the year.
Starting out with “you can’t change my mind” is fine but then don’t argue for your point with arguments that can easily be debunked. Use whichever format you like better but don’t pretend that’s more than personal preference at that point.
The big argument for the iso date-time format is lexicographic ordering. If you don’t care about that, then don’t use it.
Just as a side-note: some european countries were in fact considering switching to the iso date-time format but didn’t because it would have been an inconvenience to people already familiar with different formats. Basically the “it’s better but people prefer the older format” thing we have going on in the comment sections right now.
Cheers
It’s better but people prefer the older format
The metric system has entered the chat.
don’t argue for your point with arguments that can easily be debunked.
I literally said I don’t know what a thing means (and now that you’ve explained, it’s a useless instruction to give me, since all it does is add extra steps for those of us already perfectly happy with the European format lmfao), and made no assertion beyond my personal preference, kindly get off your fucking high horse.
just nitpicking, but technically ISO 8601 does not (currently) permit the omission of the year.
if information is to be omitted, it must be done in ascending order of significance, so you can omit, in order, seconds, minutes, hours, and days.
(if you omit the month, that’s just the year left so why bother with ISO 8601 lmao)
Why would the year, the least important, need to be first?
And why are the pieces of the pyramid made so the ISO standard is the only one that looks right? ss:mm:hh:DD:MM:YYYY would also order the numbers based on length, but would look terrible if represented like that
Why would the year, the least important, need to be first?
Maybe it’s not least important for everyone?
Almost like the preference can change depending on application…
If I’m looking at a folder full of spreadsheets, one each month (or even day) for several years, and they are all titled according to YYYY-MM-DD. All you need to do is sort by filename and now you have it broken down by year, into one spreadsheet per month/day.
And only needed to click one button to sort them into an easily readable format.
I often see the year being the most important in my archive. Followed by month, then day (which is often left out because the document is monthly).
And the why; because it sorts alphabetically.
Well you read the least frequently changing part first, the year, because if you read the seconds first, then the thing’s already changed before you’ve even finished reading it. /s
You can skip the year and just do 1-26
Sometimes you need the year
Yeah it’s funny seeing everyone in here thinking only of the one specific thing they use this for, not recognizing that the most useful order can change depending on the purpose of the data.
Why would the year, the least important, need to be first?
For proper ordering for one. ISO8601 is objectively the best way to label anything that might need to be ordered based on time. This forces data points to line up properly in chronological order, and makes it easy to time slice as needed.
And why are the pieces of the pyramid made so the ISO standard is the only one that looks right?
Because it’s the only one that goes from largest value to smallest. It’s first because you start from the largest as the base (year) and work down through size to seconds.
ss:mm:hh:DD:MM:YYYY would also order the numbers based on length, but would look terrible if represented like that
Agreed. And any sort of data analysis would be so much harder
Arent there uses other than ordering files?
The ISO standard is best for ordering files, but that doesnt mean its good for other things
Its impossible to confuse it with the other 2 presented in this post so you could use it for files and use another one for other things
Edit: i may have been misunderstanding the context in which the ISO standard is claimed to be superior
Europe: 10/12/2025 USA: 12/10/2025 If you don’t have context as to which system this is, would 2025/12/10 make things less ambiguous?
To be fair, proper ISO 8601 specifies hyphens as the separator between date elements, and I don’t think I’ve ever seen a XXXX-XX-XX (with hyphens) be used for YYYY-DD-MM. Just XX-XX could perhaps be ambiguous, but fortunately that’s not allowed by the standard, and anyone using just year-day for XXXX-XX is absolutely trolling. YYYY-DDD could have a use, though should really use a separate separator to not sort together IMO. A year-week designation could possibly look like XXXX-XX, but that seems unlikely to just be dropped in that format without context, at least to my western US sensibilities.
The fact that you can’t confuse it with other formats is precisely the advantage. With any other format (besides the awful lettered month) you have to use context clues to be sure you’re reading it correctly if the day is less than 13.
I know, why don’t we all agree to agree and use every single possible format within a shared spreadsheet
Oh god it’s so true…
I’m almost 40 and now just realizing my insistence on how to structure all my folders and notes is actually an ISO standard. Way to go me.
I stumbled upon it years ago because sorting by name sorts by date. There was no other thought put into it.
It’s incredibly annoying that in clinical research we are prohibited from using it because every date must comply with the GCP format (DD mmm yyyy). Every file has the GCP date appended to the end.
