semkuCylinder volume calculator
Enter a radius or diameter and a height to calculate cylinder volume.
Calculation rules
Cylinder volume is V = πr²h. When you enter a diameter, the radius is half that diameter; zero radius or height gives zero volume.
Unit conversions use exact definitions: 1 in = 2.54 cm, 1 ft = 12 in, 1 m³ = 1,000 L and 1 US gal = 231 in³. Gallons here are US liquid gallons.
π is approximated to 40 decimal places. Results are rounded once from the unrounded calculation: the selected cubic unit to two decimal places, liters and US gallons to three, and the additional ft³ and m³ conversions to six, with ties rounded away from zero. A positive value that would round to zero is shown as less than the smallest displayed unit.
Frequently asked questions
- What is the volume for a radius of 3 in and a height of 10 in?
- The volume is 90π in³, displayed as 282.74 in³, 4.633 L or 1.224 US gal.
- Can I enter diameter instead of radius?
- Yes. Choose Diameter; the calculator divides it by two before applying V = πr²h.
- Are the gallons US or imperial gallons?
- They are US liquid gallons, defined as 231 cubic inches per gallon.
- Does this calculate a hollow cylinder?
- No. It calculates the volume of a solid cylinder from its circular base and height.
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For details, see the privacy policy in Korean.
Calculations run in your browser without sending your calculation inputs or results to the server. See “Privacy on this page” for information about access data.