Telling the Time

"Five more minutes!" "Is it lunchtime yet?" "When does the bus come?" All day long we want to know what time it is — and the round clock on the wall can tell us, once we know how to read it. It looks tricky at first because two pointers, called hands, are moving at once. But each hand has just one job, and once you know the jobs you can read any clock in the world.

A clock has the numbers 1 to 12 spaced evenly around its face, and the two hands point at them:

the short, fat hand shows the hour — what o'clock it is;
the long, thin hand shows the minutes — how far into the hour we are.

Read the short hand first to find the hour, then the long hand to find the minutes. There are four positions of the long hand that are so handy they have their own names:

long hand straight up on 12 → o'clock (a brand-new hour);
long hand on 3 (a quarter of the way round) → quarter past;
long hand on 6 (halfway round) → half past;
long hand on 9 (three quarters round) → quarter to.

And here is the magic counting rule: each number the long hand passes is 5 minutes. So the long hand on 1 means 5 minutes past, on 2 means 10 minutes past, on 3 means 15 minutes (a quarter past), and so on. Going all the way round the 12 numbers is 12 \times 5 = 60 minutes — one whole hour.

Watch them for a whole hour. The long hand zooms all the way around the face — one complete lap — while the short hand creeps from one number to just the next one. In the time the long hand does a full circle, the short hand covers only one twelfth of the face. So the long hand is moving twelve times faster! That is why the minutes (long hand) change quickly and the hour (short hand) changes slowly. If you ever catch the short hand sitting exactly between two numbers, that is your clue that the long hand is somewhere near the bottom — it is half past.

Reading a few clocks

Once you know the two jobs, every clock splits the same way. Read the short hand, then the long hand:

Short hand on 7, long hand straight up on 12 → 7 o'clock.
Short hand halfway between 9 and 10, long hand on 6 → half past 9.
Short hand just past 4, long hand on 3 → quarter past 4 (which is 15 minutes past).
Short hand near 2, long hand on 4 → that's 4 \times 5 = 20 minutes, so twenty past 2.

The three traps that catch everybody:

The short hand is the hour. It is easy to mix the hands up because the long one looks bolder — but the long hand only tells the minutes. Short = hour, every time.
At half past 3 the short hand is halfway between 3 and 4, not still sitting on the 3. The hour hand drifts forward all hour long.
For quarter to, the hour you say is the next number. "Quarter to 4" means the short hand is creeping up toward the 4 and the long hand is on the 9.

See it on a clock

Here is a real clock face. Step through it to watch the long (minutes) and short (hour) hands appear, then read off the time from the caption. Press Refresh for a brand-new time, and try to read it yourself before you check the caption.

More to wonder about

A whole hour is split into four quarters, like a pizza cut into four slices. Quarter past means one slice (15 minutes) has gone by — the long hand is on the 3. Half past means two slices (30 minutes) — the long hand is on the 6. Quarter to means three slices have gone and only one quarter is left until the next hour, so the long hand has swung round to the 9. We count it down: "a quarter to the next hour."

Imagine a number line of minutes, from 0 to 60, with a mark every 5. Now bend it round until the 60 touches the 0 again — you've made a circle! That is exactly a clock face: 0 (and 60) sit at the top on the 12, and the marks 5, 10, 15, 20… land on the numbers 1, 2, 3, 4… The long hand is just an arrow sliding along that bent number line, over and over, all day long.

the sun an owl at night The short hand goes round the clock only once every 12 hours, but a day is 24 hours long — so it makes two trips. That means 3 o'clock comes round in the afternoon when the sun is up, and again in the middle of the night when the owl is awake. To tell them apart, grown-ups say 3 in the morning (am) or 3 in the afternoon (pm). Same hands, same clock — the sun and the owl tell you which one we mean.

Reading a few clocks

See it on a clock

More to wonder about

See it explained