24:00:00 -

Many programming languages and digital devices do not allow "24:00:00" as a valid input, automatically defaulting it to "00:00:00" of the next day.

Bus or train timetables may show 00:00 as a departure time (starting the day) and 24:00 as an arrival time (ending the day). 24:00:00

Used to mark the very start of a new calendar day. Many programming languages and digital devices do not

If you are converting between the 24-hour and 12-hour clock, use this quick reference: 24-Hour Format 12-Hour (AM/PM) Equivalent 12:00:00 AM Start of the day 12:00:00 12:00:00 PM Midday / Noon 23:59:59 11:59:59 PM Last second of the day 24:00:00 12:00:00 AM End of the day (transition point) 4. Modern Standards & Limitations 24:00:00