Midnight, in everyday timekeeping, starts at 00:00 (12:00 a.m.) local time and is treated as the first moment of a new calendar day in that time zone.

Where “midnight” actually starts

  • On a clock, midnight is the instant when the date changes from one day to the next, e.g., from 23:59:59 on March 3 to 00:00:00 on March 4.
  • In the 24‑hour system, that moment is written as 00:00 and is conventionally the start of the new day, not the end of the old one.
  • In the 12‑hour system, people often call it 12:00 a.m., but “a.m./p.m.” at midnight is technically ambiguous, which is why many standards prefer 24‑hour notation instead.

A simple way to picture it: 11:59 p.m. still belongs to “today”; one second later, at 00:00, you’re in “tomorrow”.

Why there’s confusion

  • Midnight is both the end of one civil day and the beginning of the next, so it resists being labeled as only one or the other.
  • In casual speech, people might say “midnight Friday” and mean either the very start of Friday (00:00 at the beginning) or the very end of Friday (24:00 leading into Saturday), depending on context.
  • Because of this, for schedules and legal times, it’s safer to say things like “11:59 p.m. Friday” or “00:01 a.m. Saturday” instead of a bare “midnight”.

Does midnight depend on location?

Yes. Midnight is tied to your time zone :

  • Every time zone has its own 00:00, so midnight “starts” at different absolute moments around the globe.
  • Within a time zone, midnight is the same instant everywhere; between time zones, midnight in one place may still be the previous day in another.

If you zoom out to astronomy, there’s also “solar midnight” (when the Sun is furthest below the horizon), which can differ from clock‑midnight because of time zones and daylight saving time.

A quick in‑world example (gaming)

You might also see “where does midnight start?” used in games as a location hint: for example, a World of Warcraft discussion describes an in‑game “Midnight” starting quest you begin near Stormwind Cathedral for Alliance players, or in Orgrimmar’s Valley of Strength for Horde players. In that context, “where midnight starts” is about where to go, not what time it is.

TL;DR: Midnight starts at 00:00 local time and is treated as the first instant of the new day in that time zone, even though in everyday language people sometimes treat it as the end of the old one.