UtilityBaseCalculators
Geometry Calculator
Find area, perimeter, surface area, and volume for circles, triangles, cylinders, spheres, and more.
Updated July 10, 2026
How to use the geometry calculator
- 1Choose a 2D shape or 3D solid.
- 2Enter its dimensions.
- 3Read the area/perimeter or surface area/volume.
- 4Check the formula and diagram.
Common uses
- Finding the area of a circle or triangle
- Calculating the volume of a cylinder or sphere
- Geometry homework with formulas shown
- Sizing material for a project
Frequently asked questions
How do I find the area of a circle?
The area of a circle is π times the radius squared: A = πr². For a radius of 5, that's π × 25 ≈ 78.54. Enter the radius and the calculator shows the area, circumference, and diameter with the formula.
What's the formula for the volume of a cylinder?
Volume equals π times the radius squared times the height: V = πr²h. The calculator also gives the surface area, 2πr(r + h), and draws a labeled cylinder.
Does it show the working?
Yes. Each result lists the formula it used, so you can see how the number was derived, helpful for homework and for checking your own math.
About this tool
The geometry calculator computes the key measurements of common 2D shapes and 3D solids. Pick a shape, circle, rectangle, triangle, square, cylinder, sphere, cone, or rectangular prism, enter its dimensions, and it returns the area and perimeter, or the surface area and volume, each with the formula it used and a labeled diagram. It's built for students and anyone who needs the area of a circle or volume of a cylinder quickly. Everything is calculated in your browser.
Like most tools on UtilityBase, the geometry calculator runs entirely in your browser. Nothing you enter is uploaded or stored on a server. It's free to use with no account required. Browse more calculators here.
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