Converting numbers to dates, hours and minutes (10 digits before comma, 4 after)

And what dates and times are you expecting to get, and why?

You have given not one example of what you are looking to achieve ...

Based on what I learned in this thread: https://www.excelforum.com/excel-for...ml#post5426932 these look like "seconds since Jan 1 1970" time stamps. Assuming that is the case, I tried a similar formula as I proposed in the other thread =CONVERT(timestamp,"sec","day")+DATE(1970,1,1) and I get a bunch of morning of 4 Jan 2021 timestamps.

That's my guess. If I guessed wrong, help us understand exactly what these timestamps represent and we should be able to help convert them into Excel's date/time serial number system (days since 0 Jan 1900).

Edit to add: with this assumption, 4 digits past the decimal point implies that the timestamps are to the nearest tenth of a millisecond. I seem to recall trying to format times beyond the nearest millisecond and Excel would not do it (I don't have Excel to test on right now) -- hh:mm:ss.000 was a valid number format, but hh:mm:ss.0000 was not. Can anyone with Excel handy double check?

For completeness, I went ahead and tested in my older version of Excel, and confirmed that (my version) of Excel cannot display fractions of a millisecond as part of a date/time format. I note that LO Calc is not limited to milliseconds, but can display any fraction of a second (though one is eventually limited to 15 digits of double precision in the underlying serial number value).

If you are not worried about anything past the nearest millisecond, then the solution as provided should work fine. If you ever need to be concerned with those last two digits (and the possible floating point errors in those last one to two digits), you may need to look into this a little further.