Quadrilateral Area Calculator

Area is a numerical characteristic of a two-dimensional (flat or curved) geometric figure, informally speaking, showing the size of this figure. Historically, the calculation of the area was called quadrature. A figure having an area is called quadratic. Find the area of more than 22 shapes (triangle, square, pentagon, etc.) using our amazing calculator.

Quadrilateral — is a geometric figure (polygon), consisting of four points (vertices), none of which lie on one straight line, and four segments (sides) connecting these points in series. Distinguish between convex and non-convex quadrilaterals: a non-convex quadrilateral can be self-intersecting. A quadrangle without self-intersections is called simple. Often the term “quadrangle” refers only to simple quadrangles.

The area of a quadrangle is considered as the sum of the areas of the triangles into which the diagonals divide it. Then the area of the quadrangle will add up to the semi-product of the diagonals by the sine of the angle that is given, since the parts of the diagonals are grouped and fold back in the same way as we decomposed them, and the sine of this angle and the angle complementing it are equal by definition.