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Volume of a regular octahedron calculator

Enter the dimensions of a regular octahedron and read off its volume and surface area. Volumes convert to litres and gallons with the unit selector.

Volume
30.169 889m³
≈ Rounded Volume of a regular octahedron
Surface area
55.425 626
Show the working
  1. Edge length = 4
  2. Volume = sqrt(2) / 3 * 4^3 = 30.1699
  3. Surface area = 2 * sqrt(3) * 4^2 = 55.4256

Values are shown to six significant figures here; the arithmetic itself runs on exact fractions and is only rounded where a number is printed.

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    The formula

    • volume = (sqrt 2 / 3) e^3
    • surface area = 2 sqrt 3 e^2

    Switch the volume unit to litres or US gallons to read the capacity directly.

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