Military time converter

The rule, in one sentence

From 1 PM onwards, add twelve to get military time; from 1300 onwards, subtract twelve to get PM time. Everything before noon keeps the same number with a leading zero, and the only two special cases are midnight and noon themselves.

The full clock

Midnight and noon, the only genuinely confusing part

AM means ante meridiem, before midday; PM means post meridiem, after midday. Midday itself is neither, and midnight is the boundary between two days. The convention that 12 PM is noon and 12 AM is midnight is arbitrary, universally misremembered, and the reason a hotel checkout "at 12 AM" is a support ticket waiting to happen.

The 24-hour clock removes the ambiguity entirely, which is exactly why hospitals, airlines, emergency services, railways and the military all use it. Midnight at the start of a day is 0000; some organisations write 2400 for midnight at the end of a day, and both refer to the same instant. Written schedules generally prefer 0000 for a start and 2359 for an end so there is nothing left to interpret.

How it is spoken

• 0600 — "zero six hundred" or "oh six hundred".
• 1430 — "fourteen thirty".
• 1000 — "ten hundred hours". Note there is no "o'clock" and no colon.
• 0007 — "zero zero zero seven", seven minutes past midnight.

Strictly, "hundred hours" is used for whole hours only. Adding "hours" to a time with minutes — "fourteen thirty hours" — is common in films and rare in practice.

Time-zone letters

Military and NATO usage often appends a single letter naming the time zone, so a time is unambiguous anywhere on earth. Z ("Zulu") is UTC and is the one you will meet most often, in aviation, shipping and log files. J ("Juliet") means local time wherever the reader is. The letters A through M (excluding J) run east of Greenwich and N through Y run west.

This page converts notation, not offsets — 1430Z and 1430 local are different instants, and turning one into the other needs a time zone converter.

The 24-hour clock outside the military

Most of the world simply calls it "the clock". It is standard civilian notation across continental Europe, Latin America, much of Asia and Africa, and it is the ISO 8601 standard for written time. The "military" label is largely an American English artefact, because the US, UK, Canada, Australia and a handful of other English-speaking countries kept 12-hour notation in everyday use.

There is one genuine difference: the 24-hour civilian clock is written with a colon (14:30) and the military convention drops it (1430). Both are accepted in the input above, and both are shown in the result.

Converting a list

Paste a column of times and each line is converted in the opposite direction to the way it was written — 24-hour entries come back as AM/PM, AM/PM entries come back as 24-hour — so a mixed roster or log comes out consistent. Minutes after midnight are shown alongside, which is the form you want for sorting or for arithmetic in a spreadsheet.

No network, no upload

This page is static HTML with a small JavaScript island. There is no server, no analytics and no external request of any kind, so a pasted duty roster or shift log stays entirely on your device. It works offline.