GCSE Maths: Perimeter & Circumference
Calculate the area and circumference of circles and semicircles. Practise it with adaptive questions for AQA, Edexcel, OCR and Eduqas.
What you need to know
The concepts examiners test on perimeter & circumference, and what each one is really asking.
Where marks get lost
The exam technique that separates a correct method from a correct answer.
- Using the diameter instead of the radius for the area formula
- Squaring the pi as well as the radius (it's π × r², NOT (πr)²)
- Forgetting to add the straight edge when finding the perimeter of a semicircle
- Confusing the area and circumference formulas (Cherry Pie Delicious, Apple Pies are too)
Perimeter & Circumference questions students ask
Is Perimeter & Circumference on the Foundation paper?
Yes. Perimeter & Circumference appears at both Foundation and Higher tier, though Higher papers take it further.
What should I know before starting Perimeter & Circumference?
It builds on Squaring numbers and Multiplying decimals. If those feel shaky, practise them first — Perimeter & Circumference questions assume them.
What is the most common mistake in Perimeter & Circumference?
Using the diameter instead of the radius for the area formula.
Which exam boards cover Perimeter & Circumference?
All four we support — AQA, Edexcel, OCR and Eduqas. GCSE Maths subject content is set by the DfE, so the topic is common to every board; what changes is the paper structure and the grade boundaries.