How to explain 12-hour and 24-hour time in reading and calculating time to your child
27 October 2026
Children often see time shown in both 12-hour and 24-hour formats. Understanding how to switch between these two systems is a key skill for 11+ maths and everyday life. Here's a clear, step-by-step example to help your child practise converting times.
Worked example
Question: What is 3:45 pm in 24-hour time?
Step 1: 3:45 pm is in the afternoon, so we add 12 to the hour.
Step 2: 3 + 12 = 15
Step 3: The minutes stay the same, so we keep 45.
Step 4: Write the time as 15:45.
The correct answer is 15:45.
| Step | Working |
|---|---|
| 1 | 3:45 pm is in the afternoon, so we add 12 to the hour. |
| 2 | 3 + 12 = 15 |
| 3 | The minutes stay the same, so we keep 45. |
| 4 | Write the time as 15:45. |
After seeing this worked example, your child will recognise how to convert an afternoon time from the 12-hour clock to the 24-hour clock. The same method applies to similar questions, and they can now try more practice to build confidence.
