Composite Area Calculator

Build a composite area from rectangles, triangles, circles, trapezoids, and parallelograms, including cut-outs that subtract from the total.

Add included pieces and subtract cut-outs. Every part uses the same generic length scale.

Part audit, scale & export

Review every signed component behind the total, apply a drawing scale to the finished area, and export the part ledger for checking.

Linear scale factorOutput unit label

—Raw signed area

—Scaled area (factor²)

—Added area

—Subtracted area

Part	Operation	Shape	Area

Signed components assume the parts you enter represent the intended non-overlapping additions/cut-outs. Overlap between separate added shapes is not automatically de-duplicated.

Use consistent measurements and valid geometric assumptions

Keep linear inputs in a consistent unit, verify that side lengths or coordinate points can form the stated shape, and treat sketches as explanatory unless explicitly marked to scale. Coordinate formulas can become unstable for nearly degenerate shapes, so invalid or nearly collinear inputs are rejected rather than silently returning misleading values.

How to use this Composite Area Calculator

Build a composite area from rectangles, triangles, circles, trapezoids, and parallelograms, including cut-outs that subtract from the total.