My stupid ass read this top to bottom and I was confused why anyone would start with seconds
All my homies hate ISO, RFC 3339 for the win.
All my homies hate ISO
Said no-one ever?
Nah, ISO is a shit organization. The biggest issue is that all of their “standards” are blocked behind paywalls and can’t be shared. This creates problems for open source projects that want to implement it because it inherently limits how many people are actually able to look at the standard. Compare to RFC, which always has been free. And not only that, it also has most of the standards that the internet is built upon (like HTTP and TCP, just to name a few).
Besides that, they happily looked away when members were openly taking bribes from Microsoft during the standardization of OOXML.
In any case, ISO-8601 is a garbage standard.
P1Yis a valid ISO-8601 string. Good luck figuring out what that means. Here’s a more comprehensive page demonstrating just how stupid ISO-8601 is: https://github.com/IJMacD/rfc3339-iso8601P1Y is period notation. It means a Period of 1 Year. It actually makes decent sense tbh.
Sure, it means something, and the meaning is not stupid. But since it is the same standard, it should be possible to be used to at least somehow represent the same data. Which it doesn’t.
I think it is reasonable to say: “for all representation of times (points in time, intervals and sets of points or intervals etc) we follow the same standard”.
The alternative would be using one standard for points in time, another for intervals, another for time differences, another for changes to a timezone, another for …
The alternative would be
More reasonable, if you ask me. At least I came to value modularity in programming, maybe with standards it doesn’t work as good, but I don’t see why
Standards are used to increase interoperability between systems. The more different standards a single system needs the harder it is to interface with other systems. If you have to define a list of 50 standard you use, chances are the other system uses a different standard for at least one of them. Much easier if you rely on only a handful instead
if i am not wrong, it is because essentially both are same (slight differences in what is allowed and what is not, https://github.com/IJMacD/rfc3339-iso8601), but RFC is more free as in freedom
Thx i take that back
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.
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"
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.
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
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.
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
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 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.
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 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…
In one work report, I recorded the date as “1/13/25”, “13/1/25” and “13JAN2025”
I have my preference, but please for the love of all that is fluffy in the universe, just stick to one format…
“13.1.25”, not “13/1/25”.
Let’s do it!
YYYY.MM.DD HH.MM.SS, as eru ilúvatar intended
I think I went to high school with that guy.
YYYY-MM-DD HH:MM:SS
Ftfy
MM ≠ MM !!!
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)_/¯
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…?
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
Thank you! 😂
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)_/¯
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
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.
It’s better but people prefer the older format
The metric system has entered the chat.
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
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)
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.
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.
This pyramid visualisation doesn’t work for me, unless you read time starting with seconds.
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
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
“Europe”, as if there weren’t several languages in Europe with different date formats per language…
None of which start with the month because that would be fuckin stupid
Meh. It’s getting a lot of hate here, but I think it works well in casual short term planning. Context (July) - > precision (15).
If I want to communicate the day in the current month, I just say the day, no month.
ok but by that logic you’d start with the year
No because the year is a super large time; there’s a reason people always say they take a bit to adjust to writing the new year in dates because it’s s long enough period of time that it almost becomes automatic.
For archiving, sure; most other things, no (logically, ISO-8601 is probably the best for most cases, in general, but I’ll die on the hill that MM-DD-YYYY is better than DD-MM-YYYY).
Exactly. It would be like reading the minute of the clock before the hour.
well either you omit the year, or you start with it
americans start with the month and end with the year, which is totally wild
well either you omit the year, or you start with it
Why? Because you say so?
Because “context -> precision” is exactly the reason someone earlier gave as reasoning for the American system?
Because it’s consistent that way. Why not is the real question?
Everyone starts sentences with a capital letter, you shouldn’t be flinging shit mate 😂
nahh f that shit
Again, – within most use cases – it really isn’t.
In your day to day, will you need to know the year of a thing? Probably not; it’s probably with the year you’re currently in.
Do you need to know the day of the month first? Probably not unless it’s within the current month so you need to know the month first.
Telling me “22nd” on a paper means nothing if I don’t know what month we’re referring to; and, if I do need to know the year, – well – it’s always at the the of the date so it’s easy to locate rather than parsing the middle of the date, any.
In your day to day, will you need to know the year of a thing? Probably not; it’s probably with the year you’re currently in.
that’s why I said you could omit it. did you read what I wrote?
the year is a super large time
Not when you’re old… I’ll be 50 this year, they’re flying by.
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)
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.
