Use this geometry calculation when the shape, dimensions, coordinate system, and units match the stated ideal Euclidean model.

Original area

Required number input.

Scale factor

Required number input.

Compute the new area when a shape's linear dimensions are scaled by a factor. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Scaled area

The resulting scaled area returned as a number.

• The result assumes exact idealized geometry. Measurement uncertainty, rounded inputs, nonplanarity, self-intersection, thickness, curved coordinate systems, and ambiguous dimension definitions are not automatically represented.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Sketch and label the dimensions, verify unit consistency, and use coordinate or CAD methods for irregular measured shapes.

• 3D Shape Surface Area Calculator

  Calculate total exterior surface area for common three-dimensional shapes, using the Knud Thomsen approximation for ellipsoids.

• Annulus Area Calculator

  Calculate the area of an annulus from its outer and inner radii as π(R²−r²).

• Circle Calculator

  Calculate a circle's radius, diameter, circumference, and area from one known measurement.