Area Calculator
Enter your values below and click Calculate for instant results.
Calculate the area and perimeter of rectangles, triangles, circles, trapezoids, parallelograms, and ellipses.
Enter your values below and click Calculate for instant results.
Area measures the two-dimensional space enclosed by a shape, expressed in square units. Understanding area formulas is fundamental to geometry and has practical applications in construction, landscaping, flooring, painting, and many other fields.
When calculating area for real-world applications, always use consistent units throughout. If your measurements are in feet, your area will be in square feet. To convert to square yards, divide by 9. To convert to square meters, multiply square feet by 0.0929.
The area of a rectangle is length times width. A square is a special case where length and width are equal, so the area is simply the side length squared. This is the most fundamental area formula and the basis for understanding all other shapes.
A triangle's area is one-half of base times height, where height is the perpendicular distance from the base to the opposite vertex. The base can be any side of the triangle, but the height must be measured perpendicularly to whichever side is chosen as the base.
A circle's area is pi times the radius squared. The circumference (perimeter) is 2 times pi times the radius. Pi (approximately 3.14159) is the ratio of any circle's circumference to its diameter, a constant that appears throughout mathematics and physics.