24:00:00 May 2026

A store open "00:00–24:00" is open for the full 24-hour cycle.

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

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. A store open "00:00–24:00" is open for the

Used to mark the very start of a new calendar day. Used to mark the very start of a new calendar day

While the US Navy and Marines may use the "24:00" notation, most military communication regulations recommend using 23:59 or 00:01 to avoid any ambiguity regarding which date is being referenced. Format a time or date [complete guide] - Algorithms to Go