Maths & numbers
Polygon coordinate area
Calculate a simple polygon’s area from ordered coordinates.
A clear answer. Here’s how.
Uses the shoelace formula on 3–500 ordered vertices, closing the last vertex to the first. Checks for crossing, touching non-adjacent edges and repeated vertices; these are rejected. Supports a simple polygon without holes. Area is in squared coordinate units.
See a worked example
Worked example
A fixed demonstration, separate from the values you enter above.
- One x,y coordinate pair per line
0,0 4,0 4,3 0,3
Example result
- Area
- 12
- Perimeter
- 14
- Vertices
- 4
- Vertex order
- Counter-clockwise