Math

Surface Area Calculator

Total surface area of common 3D shapes: cube, box, sphere, cylinder, and cone.

Inputs

Shape

Dim 1 (a / l / r)

Dim 2 (w / h)

Dim 3 (h, if box)

Result

Surface area

131.9469

How it's calculated

Cube 6a² · Box 2(lw+lh+wh) · Sphere 4πr² · Cylinder 2πr(r+h) · Cone πr(r+√(r²+h²)).

Does cylinder area include the ends?

Yes — the formula 2πr(r + h) covers both circular ends plus the wrapped side.

Where does the cone formula come from?

π r² is the base and π r ℓ is the slant surface, where ℓ = √(r² + h²) is the slant height.

Math

Volume Calculator

Volume of common 3D shapes: cube, box, sphere, cylinder, cone, square pyramid, and capsule.

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Circle Calculator

Enter any one of radius, diameter, circumference, or area — get all four.

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Percentage Calculator

What is X% of Y, X is what % of Y, and percentage change — all in one place.

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Percent Change Calculator

Percentage increase or decrease between two numbers.