Legally, does the judgment of age need to be accurate to the hour, whether it is a nominal age or a full one?

Legally, age is calculated by one year old, which has nothing to do with time. As long as you are born on that day, no matter what time you are on this day, it is calculated on this day, not your birthday!

For example, if you were born on the 3rd, 1992, 1 1, then 20 10/1,3rd is your18th birthday, but legally.