# Using 0 o'clock with a 12-hour clock system

**URL:** <https://boards.straightdope.com/t/using-0-oclock-with-a-12-hour-clock-system/930293>\
**Category:** Miscellaneous and Personal Stuff I Must Share\
**Created:** [January 11, 2021, 9:59pm UTC](https://boards.straightdope.com/t/using-0-oclock-with-a-12-hour-clock-system/930293 "2021-01-11T21:59:24Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![Roderick\_Femm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/roderick_femm/32/14875_2.png) [@Roderick\_Femm](https://boards.straightdope.com/u/Roderick_Femm)\
**Post date:** [January 11, 2021, 9:59pm UTC](https://boards.straightdope.com/t/using-0-oclock-with-a-12-hour-clock-system/930293/1 "2021-01-11T21:59:24Z")

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I have occasionally seen cases where a time like 12:47 am is referred to as 00:47 am, with the colon, and on a clock that is otherwise using 12-hour clock conventions.

I can’t remember specifically where I’ve seen it, it might be on Japanese TV. I live in the US.

Is this a common thing in some other countries? I don’t think I’ve seen it here, but again, it’s just something I have noticed in passing and was curious about. Frankly, it seems like a good idea to me.