There is no universally agreed upon definition. This is why some may use either 12:01 AM or 12:01 PM to avoid ambiguity. Or “12 noon” and “12 midnight”. Of cour

There is no universally agreed upon definition. This is why some may use either 12:01 AM or 12:01 PM to avoid ambiguity. Or “12 noon” and “12 midnight”. Of course, the “obvious” answer is to just use 00:00 and 12:00. Lots of folks here are trying to logically determine which use is “correct”, but it doesn’t really matter much if the reader doesn’t agree and misinterprets. So the best option is to use an unambiguous alternative like above. For more, see https://en.wikipedia.org/wiki/12-hour_clock#Confusion_at_noon_and_midnight https://en.wikipedia.org/wiki/12-hour_clock#Confusion_at_noo...