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Area Calculator Tool

Pick a shape, enter the dimensions, and instantly get the area plus perimeter or circumference.

Last updated: 2026/10/16 Calculator Feedback & bug reports
Shape & Dimensions
Result

How to Use

1

Choose a Shape

Select the shape you want to measure from the dropdown, such as rectangle, triangle, or circle.

2

Enter Dimensions

Type in the required side lengths or radius for the chosen shape and the result is calculated instantly.

3

Check & Copy

See the area along with perimeter or circumference, and copy the result with one click.

About the Area Calculator

A web tool that instantly calculates the area of common shapes: rectangle, square, triangle, parallelogram, trapezoid, circle, and sector. It also shows perimeter, circumference, and arc length. All calculations run in your browser, so the values you enter are never sent to any server.

Features

  • 7 Shapes SupportedRectangle, square, triangle, parallelogram, trapezoid, circle, and sector.
  • Area + PerimeterGet the area together with perimeter, circumference, or arc length.
  • Real-time CalculationResults update the moment you type. No button needed.
  • Privacy ProtectedAll processing happens in your browser. Numbers are never sent to servers.

Use Cases

  • Room, land, and garden area
  • Checking math homework and tests
  • Estimating wallpaper, paint, or tile quantities
  • Material sizing for DIY and crafts
  • Double-checking design and blueprint figures

FAQ

Is the area calculator free to use?
Yes, it is completely free. No registration or installation is required. Just open it in your browser and start calculating.
How are units handled?
The unit is used only as a display label. As long as your inputs share the same unit, the area is shown in that unit squared (e.g. cm²) and the perimeter in the same unit. Avoid mixing different units in one calculation.
How is the triangle area calculated?
It uses base x height / 2. Enter the height measured perpendicular to the base. If you only know the three side lengths, you will need to derive the height separately.
Is the sector angle entered in degrees?
Yes, enter the central angle in degrees. From the radius and angle, the tool computes the area, arc length, and perimeter (arc plus two radii).
Are the values I enter stored anywhere?
No. Every calculation runs entirely in your browser, and the values you enter are never sent to or stored on any server. You can use it with peace of mind.

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