plotarea.

ORDERED CORNERS / ONE SIMPLE OUTLINE

Trace the corners.
Measure the shape.

Turn local x,y coordinates into an irregular footprint’s area and boundary length. Keep the entered order, check the outline, and see the arithmetic.

Free and browser-local. No maps, uploads or account.

Illustrative concave outline with six cornersILLUSTRATIVE LOCAL PLAN · NOT A MAP

01 / DEFINE YOUR OUTLINE

Walk around the edge.

Every x and y uses this unit. Changing units converts the list while preserving unedited physical coordinates.

Use 3–100 distinct vertices. Start at any corner and continue clockwise or counterclockwise. The last point closes to the first automatically; one final repeat of the first is also accepted.

Signed plain decimals, up to 12 decimal places. Use commas between x and y; no headings or interior blank lines. Coordinate magnitude is limited to 1,000,000,000 metres equivalent.

One local, flat outline. Crossings, boundary touches and overlaps are rejected before usable results appear.

02 / CHECK YOUR FOOTPRINT

Area inside.
Length around.

CONCAVE DOES NOT MEAN INVALID

An inward corner
still belongs
to the outline.

The default L-shape encloses 6 m². Its 4-by-3 m bounding rectangle covers 12 m², including a missing section that is outside the actual footprint.

Plotarea checks that edges form one simple boundary, then uses ordered coordinates to count the area inside it. It does not rearrange your points or fill in a concave corner.

Follow the area, perimeter and topology examples →