Geometry & Shapes
Surface Area Calculator
Surface Area: it applies the surface-area formula for the solid you choose. Worked through below with real figures, and the calculator repeats the working on your own inputs — free, on-device, instant.
Enter your shape, side or radius, height or depth and width and Surface Area Calculator works out the surface area with the surface-area formula for the solid — fast, free and private, with no sign-up or uploads.
About this calculator
It applies the surface-area formula for the solid you choose. It matters whenever a shape has to be measured, cut, covered or compared and the geometry has to be right first. Worked below as Surface area of a 3 m cube = 6 × 3² = 6 × 9 = 54 m² . — and the calculator on this page repeats exactly that working for your inputs, instantly, and offline after load.
How to use
- Choose the shape you want.
- Fill in the dimensions for that shape.
- Press Calculate to find the surface area.
- Read the surface area.
Why use Surface Area Calculator
Fast
Calculations run in your browser. No round trip to a server.
Private
Your inputs never leave your device. Nothing is uploaded.
Free
No signup, no paywall, no ads-in-results, no watermarks.
Accurate
Uses standard formulas for quick educational estimates; check critical results before relying on them.
Mobile-ready
Optimised for phones, tablets, and desktops alike.
Transparent
Honest disclaimers wherever browser limits or regional rules apply.
Common uses
Use it for packaging surface estimates
Use it when checking a shape's outer area
Use it for geometry homework
Use it for cladding and plating area
Use it for wrapping or covering a solid
Use it for a quick surface-area check
Technical notes
Surface Area Calculator applies the surface-area formula for the solid you choose.
Results assume exact, idealised shapes; real-world measurement error is not included.
Nothing you type is uploaded — the calculation happens entirely on your device.
FAQ
Which shapes are supported?
It covers a cube, sphere, cylinder, cone, and rectangular box; pick the shape, then enter its dimensions.
Do I need to fill in every dimension?
No. Only the fields relevant to the chosen shape are used; the others are ignored.
How is a cone's surface area found?
It adds the curved surface and the base: πr(r + slant height), where the slant height comes from the radius and height.
Does the Surface Area Calculator send my data to a server?
No. The Surface Area Calculator runs entirely in your browser, so nothing you enter is uploaded, stored, or shared.
Worked example
Surface area of a 3 m cube = 6 × 3² = 6 × 9 = 54 m².