Time in words.

02 · the flip

Past becomes to at the half hour.

Up to thirty minutes, the time is counted forward from the hour just gone. After thirty, it is counted backward from the hour coming. Two things change at that point, and forgetting the second one is the usual error.

So 2:45 is "quarter to three". The hour in the phrase is not the hour on the clock, which is why "quarter to two" for 2:45 is the mistake people actually make. The digital reading has no such problem — 2:45 is "two forty-five" — and that is part of why it took over on screens.

05 · the two clocks

Twelve hours, or twenty-four.

English-speaking countries are unusual in keeping the twelve-hour clock for everyday use. Most of the world writes 14:30, and the a.m./p.m. suffix looks to them like extra machinery bolted onto a number that did not need it. Both systems are in use in English, and they belong in different places rather than competing.

The twelve-hour clock wins in speech and in anything conversational: nobody says "let us meet at fourteen thirty" over lunch. The twenty-four-hour clock wins wherever a mistake is expensive — timetables, medical records, aviation, the military, server logs — because it cannot be misread by twelve hours, which is the one error the other system permits.

Reading the twenty-four-hour clock aloud has its own conventions. In ordinary speech people convert: 14:30 becomes "half past two". In the services and in aviation the digits are read directly — "fourteen thirty", and a whole hour becomes "fourteen hundred". What nobody says, in any register, is "fourteen o'clock": the word attaches to the twelve-hour clock and does not travel.

One notational detail worth getting right: midnight is 00:00 at the start of a day and 24:00 at the end of one, and both are valid in ISO 8601. They name the same instant and belong to different dates, which is exactly the ambiguity the twelve-hour clock has with 12 a.m. Written as 00:00 with a date attached, it is unambiguous.

07 · questions

Frequently asked questions.

1. Q01

   How do you tell the time in English?

   Two ways, both standard. The conversational form counts from the nearest hour: half past two, quarter to three, ten past five. The digital form reads the clock face: two thirty, two forty-five, five ten. Neither is more correct; the first is more common in speech, the second in anything read from a screen.

2. Q02

   When does it change from "past" to "to"?

   At the half hour. Up to and including :30 the minutes are past the hour just gone; from :31 they are to the hour coming. Crossing that line also changes which hour you name — 2:45 is "quarter to three", not "quarter to two".

3. Q03

   Is 12 a.m. noon or midnight?

   Midnight, strictly, since a.m. means before midday. But the question gets asked so often that the answer is unreliable in practice, and many style guides tell writers to avoid both 12 a.m. and 12 p.m. entirely. On anything that matters, write "noon" or "midnight", or shift the time to 12:01.

4. Q04

   When do I use "o'clock"?

   Only on the exact hour, and only in the twelve-hour clock: three o'clock, but never "three fifteen o'clock" and never "fifteen o'clock". It is a contraction of "of the clock", which is why it attaches to nothing but a whole hour.

5. Q05

   How do I read 24-hour times?

   Either convert to the twelve-hour clock — 14:30 is "half past two in the afternoon" — or read it as the military convention does: "fourteen thirty", or "fourteen hundred" for a whole hour. What you cannot say is "fourteen o'clock".

6. Q06

   What is the difference between a.m./p.m. and the 24-hour clock?

   Coverage and ambiguity. The 24-hour clock has one string for every minute of the day and needs no suffix; the twelve-hour clock needs a.m. or p.m. and still leaves noon and midnight contested. Most of the world uses 24-hour time in writing; the United States, Canada, Australia and the UK largely keep the twelve-hour clock outside technical contexts.

7. Q07

   Do I write "half two" like the British do?

   Only if your reader is British. "Half two" means 2:30 in British English, dropping the "past". It is not used in American English, and in German the identical-looking construction means 1:30 — half of the way to two — which makes it a genuinely risky abbreviation across languages.

8. Q08

   Why do some people say "a quarter of three"?

   It is a regional American form, heard mostly in the north-east, and it means 2:45 — the same as "quarter to three". Outside that region it puzzles people, because "of" suggests possession rather than subtraction. If your reader is not local, "quarter to" travels better.

9. Q09

   How precise should a written time be?

   As precise as the thing being scheduled. Rounding to the nearest five minutes is normal for meetings and reads as approximate, which is usually honest. Writing 14:37 signals that the exact minute matters, so only write it when it does — a departure, a deadline, a log entry.

10. Q10

    How does telling the time differ in Spanish and Portuguese?

    Both use the verb "to be" in the plural for most hours and treat the hour as feminine — son las dos y media. Both also count minutes past and to, with the flip at the half hour, so the structure will feel familiar. Each has its own page on this site.