Area Calculator
Area formulas vary by shape. Rectangle: length × width. Triangle: (base × height) / 2. Circle: π × radius². Trapezoid: ((base1 + base2) / 2) × height. For example, a 10×12 ft rectangle = 120 sq ft. A circle with 5 ft radius = 78.54 sq ft. Convert between units: 1 sq ft = 0.0929 sq m, 1 acre = 43,560 sq ft, 1 hectare = 10,000 sq m.
Calculate area and perimeter for rectangles, circles, triangles, trapezoids, ellipses, parallelograms, and regular polygons. Visual shape diagrams, formula display, and unit conversion between sq ft, sq m, sq in, sq cm, acres, and hectares.
Shape
Dimensions
Diagram
Units
How to Use
- Enter your value in the input field
- Click the Calculate/Convert button
- Copy the result to your clipboard
Frequently Asked Questions
- How do I calculate the area of a rectangle?
- The area of a rectangle is calculated by multiplying its width by its height: A = width × height. For example, a rectangle that is 10 feet wide and 8 feet tall has an area of 80 square feet. The perimeter is P = 2 × (width + height).
- How do I calculate the area of a circle?
- The area of a circle is A = π × r², where r is the radius. For example, a circle with radius 5 has an area of π × 25 ≈ 78.54 square units. The circumference (perimeter) is C = 2 × π × r ≈ 31.42 units.
- How do I calculate the area of a triangle?
- The area of a triangle is A = ½ × base × height, where height is the perpendicular distance from the base to the opposite vertex. For example, a triangle with base 12 and height 8 has an area of 48 square units. For perimeter, add all three sides.
- How do I convert square feet to square meters?
- To convert square feet to square meters, multiply by 0.0929. For example, 500 sq ft = 500 × 0.0929 = 46.45 sq m. To convert square meters to square feet, multiply by 10.764. Our calculator converts between sq ft, sq m, sq in, sq cm, acres, and hectares.
- What is the formula for the area of a trapezoid?
- The area of a trapezoid is A = ½ × (a + b) × h, where a and b are the two parallel bases and h is the height (perpendicular distance between them). For example, with bases of 6 and 10 and height 4: A = ½ × 16 × 4 = 32 square units.
- How do I calculate the area of a regular polygon?
- The area of a regular polygon is A = (n × s²) / (4 × tan(π/n)), where n is the number of sides and s is the side length. For a regular hexagon with side 5: A = (6 × 25) / (4 × tan(π/6)) ≈ 64.95 square units. The perimeter is simply P = n × s.