Area Calculator
Calculate the area of any 2D shape — circle, square, rectangle, triangle, trapezium, parallelogram or kite — with full step-by-step working. Select a shape, enter the measurements, and get an instant result with the formula clearly shown.
Area of Rectangle
40 units²
How it works
Write the formula
Area of a rectangle = length × width.
Substitute and calculate
A = 8 × 5 = 40 square units.
Result:40 units²
Area formulas
Worked examples
Find the area of a rectangle with length 8 cm and width 5 cm.
- 1Formula: A = l × w
- 2Substitute: A = 8 × 5
- 3Calculate: 40 cm²
Find the area of a triangle with base 10 m and height 6 m.
- 1Formula: A = ½ × b × h
- 2Substitute: A = ½ × 10 × 6
- 3Calculate: 30 m²
Find the area of a circle with radius 7 cm.
- 1Formula: A = πr²
- 2Substitute: A = π × 7² = π × 49
- 3Calculate: ≈ 153.94 cm²
Frequently asked questions
How do you find the area of a triangle?+
Area = ½ × base × height. The height must be perpendicular to the base.
What is the area of a circle?+
Area = πr², where r is the radius.
How do you find the area of a trapezium?+
Area = ½(a + b)h, where a and b are the parallel sides and h is the perpendicular height.
How do you find the area of a parallelogram?+
Area = base × perpendicular height (not the slant side).
What is the area of a rectangle?+
Area = length × width.
How do you find the area of a compound shape?+
Split the shape into simpler shapes (rectangles, triangles), find each area separately, then add or subtract.