Calculate the area of 8 common geometric shapes — rectangle, square, circle, triangle, trapezoid, parallelogram, rhombus, and ellipse. Instant results with formulas shown. Pure client-side.
Rectangle: length × width
Circle: π × radius²
Triangle: ½ × base × height
This area calculator computes the area and perimeter of 8 common geometric shapes. Simply select a shape, enter the required measurements, choose your unit system, and get instant results with the formula used. All calculations happen in your browser — no data is sent to any server. Perfect for students, engineers, designers, and anyone who needs quick geometry calculations.