Geometry Calculator
Calculate area, perimeter, and volume. See a visual preview of your shape.
Try it with this example
Select "Circle", enter radius 5, and see area and perimeter. Try "Sphere" with radius 3 for volume.
What is this tool?
The Geometry Calculator computes area, perimeter, and volume for common 2D shapes and 3D solids. Whether you need the area of a circle, the perimeter of a trapezoid, or the volume of a sphere, you enter the dimensions and get instant results. Students use it for homework; engineers and designers use it for quick checks; anyone who has forgotten a formula can rely on it. No lookup tables or manual calculations—just select the shape, plug in the numbers, and read the output.
For 2D shapes, the tool supports circle, square, rectangle, triangle, ellipse, trapezoid, and parallelogram. Enter the relevant lengths: radius for a circle, base and height for a triangle, or lengths of sides for polygons. The area and perimeter update immediately. For 3D solids—sphere, cylinder, and cone—enter radius and height where applicable, and get volume and surface area. The tool uses standard formulas: πr² for a circle's area, 4/3 πr³ for a sphere's volume. Everything runs in your browser; no server calls.
A visual SVG preview accompanies each shape, so you can confirm you've selected the right figure and that your inputs make sense. This helps when dimensions might be ambiguous (e.g. which side is the base of a trapezoid). The preview scales to your inputs where possible, giving an intuitive check. If a value is missing or invalid, the tool handles it gracefully rather than breaking.
Use the Geometry Calculator when you need quick answers without writing code or opening a spreadsheet. Converting between metric and imperial? Do the conversion elsewhere first, then enter the values here. The tool stays focused: shape in, dimensions in, results out. For complex or custom shapes, a full CAD or math package may be better, but for the everyday formulas—circle, rectangle, sphere, cylinder—this covers the gap between mental math and heavyweight software.
Bookmark it for homework help, design estimates, or whenever a geometry formula slips your mind. No signup, no install, no limits.