# Universal Time vs UTC Time in Dates

**URL:** <https://discourse.julialang.org/t/universal-time-vs-utc-time-in-dates/103204>\
**Category:** General Usage\
**Tags:** dates\
**Created:** [August 25, 2023, 2:18pm UTC](https://discourse.julialang.org/t/universal-time-vs-utc-time-in-dates/103204 "2023-08-25T14:18:41Z")\
**Posts on this page:** 1\
**Showing post:** 6

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**Author:** ![dlakelan](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/dlakelan/32/8491_2.png) [@dlakelan](https://discourse.julialang.org/u/dlakelan)\
**Post date:** [August 25, 2023, 3:30pm UTC](https://discourse.julialang.org/t/universal-time-vs-utc-time-in-dates/103204/6 "2023-08-25T15:30:21Z")

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> [@\`DateTime\` arithmetic on \`Microsecond\` (or smaller) scale](https://discourse.julialang.org/t/datetime-arithmetic-on-microsecond-or-smaller-scale/102949/107):
>
> module now needs to know about leap seconds (assuming UTC timestamps).

[https://docs.julialang.org/en/v1/stdlib/Dates/#footnote-1](https://docs.julialang.org/en/v1/stdlib/Dates/#footnote-1)

Footnote notes that in the time model used for DateTime there are no leap seconds. (Edit: LOL, just realized you were the one who posted that above!) Now, if the time model used in the generation of the data has leap seconds then yeah, you’ve got issues, provided that a leap second occurred within the bounds of your dataset, which, hopefully we’ll get rid of leapseconds and then won’t have to deal with it? From what I can see there haven’t been any since 2017 or so

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