X Tables
Maths History

Why clocks count to 60

A base-60 adventure linking Babylonian maths to seconds, minutes, angles and circles.

Quick answer

Clocks count to 60 because of ancient Babylonian maths, where people used a base-60 number system. This system was so useful that we still use it today for telling time, measuring angles, and dividing circles.

Learning outcome

By the end of this page, you will understand why clocks use 60 seconds in a minute and 60 minutes in an hour, and how this connects to ancient maths. Success signs:
  • You can explain that clocks use 60 because of the Babylonians
  • You can count in 60s and 12s (like the hours on a clock)
  • You can show how 60 is made from smaller numbers (like 6 × 10 or 12 × 5)
  • You can solve simple problems using 60s and 12s

Why this matters

Knowing why clocks count to 60 helps you understand how maths grew from ancient times to help people measure time, space, and angles. This ancient idea still helps us today when we play games, cook, or even measure the sky!

How it works

The story starts with the Babylonians, who lived about 4,000 years ago. They used a number system with 60 as its base, which means they counted in groups of 60. This system was very helpful for their trade, astronomy, and land measurement. Later, people who made clocks liked this idea and used 60 seconds in a minute and 60 minutes in an hour. Let’s break it down:
  1. First, imagine a clock face with 12 numbers
  2. Each number is 5 minutes apart (because 12 × 5 = 60)
  3. Each minute has 60 seconds
  4. So, one hour = 60 minutes × 60 seconds = 3,600 seconds

Examples you can see

Let’s imagine you are making a clock with 12 numbers. Each number is 5 minutes apart. That means:
  • 12 numbers × 5 minutes = 60 minutes in an hour
  • Each number shows 5 minutes
  • So, 12 × 5 = 60
You can also think of it like this:
  • 1 hour = 60 minutes
  • 1 minute = 60 seconds
  • So, 1 hour = 60 × 60 = 3,600 seconds
Here’s a fun way to think about it:
  • Imagine you are counting 60 apples
  • Each group has 10 apples
  • How many groups do you have? 60 ÷ 10 = 6 groups
  • But 6 × 10 = 60

Try it as a mini adventure

Let’s go on a time adventure! Adventure: The Clock Builder You are a clock maker and you need to make a new clock. You have a circle and you want to divide it into 60 equal parts. You know that 60 is a big number, so you decide to break it into smaller parts. 1st time: You divide the circle into 12 equal parts (like the numbers on a clock) 2nd time: Each part is 5 minutes (because 12 × 5 = 60) 3rd time: Each minute is split into 60 seconds 4th time: So, 12 × 5 × 60 = 3,600 seconds in one hour Challenge: How many seconds are in 2 hours? Answer: 2 × 3,600 = 7,200 seconds

Common mistakes

  • Mistake: Thinking that 60 = 10 × 6, but also thinking 60 = 12 × 5
    Why it happens: Children may only see one way to make 60.
    Fix: Show that 60 can be made by 10 × 6 or 12 × 5 or 6 × 10 or 5 × 12.
  • Mistake: Confusing 60 minutes with 60 seconds
    Why it happens: Time can be confusing, especially when seconds are so small.
    Fix: Use a real clock and point to the minute hand to show 60 minutes.
  • Mistake: Thinking that 1 hour = 60 seconds
    Why it happens: The number 60 is big and can be hard to understand.
    Fix: Count together: 1 minute = 60 seconds, so 1 hour = 60 × 60 = 3,600 seconds.

Parent and carer guide

Parents and carers can help by:
  • Using a real clock to show how minutes and seconds work
  • Counting in 60s together (like 60, 120, 180, 240, 300, 360)
  • Playing a game where you count how many seconds it takes to do a simple task
  • Using a clock to show that 12 numbers × 5 minutes = 60 minutes
  • Looking at a circle and dividing it into 12 parts to show how it connects to time
How to help without pressure:
  • Ask: “How many minutes are in an hour?”
  • Encourage them to count by 5s or 10s to reach 60
  • Use everyday time to make it real: “We waited 30 minutes for the bus”
  • Keep it fun and short – 5-10 minutes of practice is enough

Practice questions

  1. How many seconds are in 1 minute?
  2. How many minutes are in 1 hour?
  3. How many seconds are in 1 hour?
  4. How many seconds are in 2 hours?
  5. How many minutes are in 3 hours?
Answers:
  1. 60 seconds
  2. 60 minutes
  3. 3,600 seconds
  4. 7,200 seconds
  5. 180 minutes

FAQ

Why do we use 60 for time?

We use 60 because the ancient Babylonians used a base-60 number system. They found it helpful for dividing time and angles into equal parts.

Can we count in 60s like 60, 120, 180?

Yes! You can count in 60s. For example, 60, 120, 180, 240, 300, 360. This helps when you are counting time or measuring large angles.

Why does the clock have 12 numbers?

The clock has 12 numbers because it helps us divide the circle into 12 parts. Each part is 5 minutes, and 12 × 5 = 60 minutes in an hour.

How does this connect to angles?

A full circle is 360 degrees. If you divide it into 60 equal parts, each part is 6 degrees. This is because 360 ÷ 60 = 6.

Is 60 the only number that works for time?

No! But 60 is a very useful number because it can be divided by many smaller numbers: 1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, and 60. This makes it easy to share time.