A cubic inch (plural: cubic inches) is a unit of volume, equal to the volume of a cube with sides of one inch. The following symbols are used to denote cubic inches:

• cubic in
• cu inches, cu inch, cu in
• inches/-3, inch/-3, in/-3
• inches^3, inch^3, in^3
• inches³ ,inch³, in³
• c.i.
• CID, for cubic inch displacement, in internal combustion engines

Cubic inches are still sometimes used as unit of measurement in the United States and the United Kingdom.

Equivalence with other units of volume

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1 cubic inch (assuming an international inch) is equal to:

• 0.0005787037037 cubic feet (1 cubic foot is equal to 1,728 cubic inches)
• about 0.554112552 U.S. fluid ounces
• about 0.069264069 U.S. cups
• about 0.000465025413 U.S. bushels
• about 0.00432900431 U.S. liquid gallons
• about 1.0307153119047619047619047619048e-4 crude barrels
• 0.016387064 litres (1 litre is about 61.02 cubic inches)
• 16.387064 cubic centimetres (1 cubic centimetre is equal to about 0.06102 cubic inches)
• 1.638704 E-5 cubic metres (1 cubic metre is equal to about 61,024 cubic inches)

Use of the cubic inch

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The cubic inch is sometimes used to express the size of engines. These examples reflect common engine sizes:

• 200 c.i. = 3.28 litres
• 350 c.i. = 5.74 litres
• 409 c.i. = 6.7 litres
• 426 c.i. = 6.98 litres
• 454 c.i. = 7.44 litres

• 1000cc = 61 c.i.
• 1600cc = 97.6 c.i.
• 2000cc = 122 c.i.

See also

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• 1 E-2 m³ for a comparison with other volumes
• Orders of magnitude (volume)
• Conversion of units
• Square inch

Units of volume | Imperial units | Customary units in the United States

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