Surface area calculator

Find the complete outside area of a box, sphere, right circular cylinder or cone.

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Shape and dimensions: box L W H, sphere R, cylinder R H, cone R H

Answer

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Find the complete outside area of a box, sphere, right circular cylinder or cone.

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Formula and assumptions

Box: 2(lw + lh + wh). Sphere: 4πr². Closed cylinder: 2πr(r + h). Closed cone: πr(r + √(r² + h²)). All faces and circular ends are included; use one length unit. Separate dimensions with spaces; 1,000 is a single dimension value.

Automatic precision shows numbers to 12 significant digits. Thousands separators such as 1,000 are accepted; use a dot for decimals.

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Updated 2026-09-26

Using Surface area calculator

Find the complete outside area of a box, sphere, right circular cylinder or cone.

Box: 2(lw + lh + wh). Sphere: 4πr². Closed cylinder: 2πr(r + h). Closed cone: πr(r + √(r² + h²)). All faces and circular ends are included; use one length unit.

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A worked example

Example inputs: shape and dimensions: box l w h, sphere r, cylinder r h, cone r h = box 4 3 2. Closed surface area = 52.

Before you use the result

Box: 2(lw + lh + wh). Sphere: 4πr². Closed cylinder: 2πr(r + h). Closed cone: πr(r + √(r² + h²)). All faces and circular ends are included; use one length unit.

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ToolOctopus. “Surface area calculator.” Updated 2026-09-26. https://tooloctopus.com/surface-area-calculator.

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