Many shapes, one tool
Squares, rectangles, circles, triangles, regular polygons, spheres, cylinders, cones, pyramids, tori and more are combined in one interface.
Geometry calculator
Solve common 2D and 3D shapes from the dimensions you know. Areas, perimeters, diagonals, angles, surface areas and volumes are calculated locally in your browser.
- 100% local
- Instant
- Free
- No account
- Works offline
Choose the shape to solve.
Square
Select the information you already have.
Select the information you already have.
Results
Results update instantly.
Enter valid dimensions to display results.
Why use this tool?
Choose a geometric shape, enter only the dimensions you know, and let the solver calculate everything that can be derived. The tool covers common 2D shapes and 3D solids with instant local calculations.
Start with what you know
When several solving methods exist, choose the dimensions you have instead of searching for a different calculator.
Instant calculation
Results update as you type: area, perimeter, diagonal, angles, surface area or volume whenever they can actually be calculated.
Built-in units
Enter lengths in millimetres, centimetres, metres, inches, feet or other common units. Results follow automatically.
Fonctionnement
How does this tool work?
The calculator behaves like a solver rather than a collection of isolated formulas. First choose the shape, then select the combination of dimensions you already know. Values are normalized to a common unit before calculation. The engine applies only the mathematical relationships supported by those inputs and returns quantities that can genuinely be derived, such as area, perimeter, diagonal, angles, surface area or volume. If the supplied information is insufficient, the calculator deliberately leaves unsupported results out.
Use cases
Solve a shape from known dimensions
Start from a radius, diagonal, several sides, a height or an angle and obtain every quantity that can be derived reliably from the available information.
Check geometry calculations quickly
Verify an area, perimeter, diagonal, angle, surface area or volume without opening several separate formula calculators or repeating the same inputs.
Work with mixed measurement units
Enter each dimension in its original unit, such as centimetres and metres, and let the tool normalize the values before performing the geometry calculation.
Guide
How to use this tool
- 1
Choose a shape
Select a 2D shape or 3D solid.
- 2
Choose what you know
For shapes with several solving methods, select the combination of dimensions you already have.
- 3
Enter the dimensions
Type the values and select their units. Available results appear immediately.
Tips and best practices
- You can mix units between fields: values are normalized before calculation.
- The solver only displays quantities that can actually be derived from the information provided.
- Angles can be entered in degrees, radians or gradians.
Frequently asked questions
Which shapes are supported?
The calculator covers many 2D shapes and 3D solids including square, rectangle, circle, triangles, trapezoid, parallelogram, rhombus, ellipse, annulus, sector, regular polygon, cube, cuboid, sphere, cylinder, cone, pyramid and torus.
Why are some results not shown?
A shape cannot always be fully determined from the available information. For example, a triangle base and height determine its area but not its perimeter. The solver therefore avoids inventing results.
Can I mix units in one calculation?
Yes. Every length field has its own unit selector. Values are converted to a common base unit before calculation.
Are calculations sent to a server?
No. All calculations run locally in your browser.
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