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Tell HN: Hacker News datetimes are falsely precise

5 pointsperilunar3 comments
On HN

I just noticed that the datetime for comments and submissions is weirdly precise. Apparently all comments happen exactly on the second, to the microsecond!

e.g. here is one from a few minutes ago: 2026-09-10T14:50:13.000000Z

This is a clear example of false precision:

https://en.wikipedia.org/wiki/False_precision

Comments

My guess is that an ordinary system date is being formatted as a string using a routine that also converts finer grained times for logging.

Which is to say there is some timeToString function that works for comment time stamps as ordinary system dates and for system event timestamps.

It is engineered to be the simplest thing that might work.

But that’s just a guess and I am often an idiot.

Indeed, it is also imprecise since the timestamp does't include the timezone. :)

Z means Zero Time (+00:00). They're UTC timestamps

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