Quadrilateral Area Calculator

Entering data into the quadrilateral area calculator

To calculate the area of a quadrilateral:

• select defined datas;
• enter the value of datas;
• select units of measurement - meter (m), centimeter (cm) or millimeter (mm);
• select in which units you want to get the area - square meters (m²), square centimeters (cm²) or square millimeters (mm²).

You can input only integer numbers or fractions in this online calculator. More in-depth information read at these rules.

If you have any difficulties with units conversion, you can use the length converter and area converter.

Additional features of quadrilateral area calculator

• Use and keys on keyboard to move between field in calculator.

Quadrilateral is a geometrical figure consisting of four points (vertices), no three of which lie on a straight line and four line segments (sides), mutually connecting these points.

Quadrilateral called convex if the segment connecting any two points of the quadrangle will be inside it.

The formulas for calculating of quadrilateral area:

●	A = 12 d1 d2 sin α
	where A - quadrilateral area, d1, d2 - length of quadrilateral diagonals, α - angle between quadrilateral diagonals.
●	A = s · r
	where A - quadrilateral area, s = a + b + c + d2 - semiperimeter of quadrilateral, r - in-radius.
●	A = √(s - a)(s - b)(s - c)(s - d) - abcd cos2θ
	where A - quadrilateral area, a, b, c, d - length of quadrilateral sides, s = a + b + c + d2 - semiperimeter of quadrilateral, θ = α + β2 - half the sum of two opposite angles of a quadrilateral.