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Area Calculator
About the Area Calculator
Calculate the area of five common shapes and see a drawing of the shape as you enter dimensions.
How to use the Area Calculator
- Choose a shape: Square, Rectangle, Circle, Triangle or Trapezoid.
- Enter the dimensions that appear (such as side, length and width, radius, base and height).
- Press Calculate area to see the area and the drawing.
Formula and method
Square: sΒ² Β· Rectangle: l Γ w Β· Circle: Ο Γ rΒ² Β· Triangle: Β½ Γ b Γ h Β· Trapezoid: Β½ Γ (a + b) Γ h
Worked example
A circle with radius 5: Ο Γ 5Β² = 78.54 square units.
When to use the Area Calculator
- Working out how much flooring, paint, turf or fabric you need.
- Finding the area of common shapes for school or work.
- Comparing plots of land or rooms.
Common mistakes to avoid
- Mixing units, for example feet for one side and inches for the other.
- Forgetting to subtract areas that will not be covered, such as windows.
- Not adding a little extra for waste when buying materials.
Tips
- Area is measured in square units (cmΒ², mΒ², ftΒ²). Keep the units consistent.
- For irregular shapes, split them into rectangles and triangles and add the areas.
Frequently Asked Questions
Square the length conversion factor. For example, 1 mΒ² = 10,000 cmΒ² because 1 m = 100 cm.
Split it into simple shapes such as rectangles and triangles, work out each area and add them up.
Area is the space inside a shape, in square units. Perimeter is the distance around its edge.