Calculate box or cylinder volume from dimensions in inches, or convert cubic inches to cubic feet, liters, US gallons, and Imperial gallons.
- All Unit Converters
- All Volume Calculators
- Inches to Square Inches Calculator
- Weight Per Volume Calculator
Calculator Functions
| Function | What it does | What it requires |
|---|---|---|
| Rectangular volume | Finds the volume of a box, tank or bag with straight sides | Requires the inside length, width and height |
| Cylinder volume | Finds the volume of a round container such as a pipe, bucket or drum | Requires the inside diameter and height |
| Convert cubic-inch volume | Converts a volume already known in cubic inches into other units | Requires the volume in cubic inches |
Each dimension can be entered in in, ft, cm or mm, and is converted to inches before the volume is worked out. Every result is given in cubic inches, cubic feet, liters, US liquid gallons, imperial gallons, cubic centimeters and cubic meters.
Inches to Volume Formulas
| V | Volume (in³) |
| L | Inside length (in) |
| W | Inside width (in) |
| H | Inside height (in) |
A length in inches is one dimension and cannot be converted to a volume on its own. Volume needs three lengths multiplied together, or an area multiplied by a depth, which is why the result is in cubic inches.
Rectangular volume
The main formula applies directly. A box that measures 10 × 12 × 18 inches inside holds 10 × 12 × 18 = 2,160 in³, which is 1.25 ft³, 35.40 L or 9.35 US gallons.
Cylinder volume
D is the inside diameter and H is the height, or the length for a cylinder lying on its side. A round container 20 inches across and 9 inches tall holds π × 10² × 9 = 2,827.43 in³, which is 46.33 L or 12.24 US gallons.
Convert cubic-inch volume
The cubic-inch figure is multiplied by the factor for each unit. The same factors turn the box and cylinder results into liters, gallons and cubic feet.
| Unit | 1 in³ equals | Basis |
|---|---|---|
| Cubic feet | 0.000578704 ft³ | 1 ft³ = 1,728 in³ |
| Liters | 0.016387064 L | 1 in = 2.54 cm |
| US liquid gallons | 0.004329 US gal | 1 US gal = 231 in³ |
| Imperial gallons | 0.00360465 imp gal | 1 imp gal = 4.54609 L |
| Cubic centimeters | 16.387064 cm³ | 2.54³ |
| Cubic meters | 0.000016387064 m³ | 0.0254³ |
These agree with the NIST factors for the cubic inch, cubic foot, US gallon and imperial gallon [2]. A US gallon of 231 in³ is 3.785412 L, so 231 in³ converts to exactly 1 US gallon and 0.8327 imperial gallons.
Limits of This Estimate
- The result is the full geometric volume of a perfect box or cylinder. Rounded corners, tapered sides, wall thickness and headspace all reduce what a real container holds.
- Inside dimensions give capacity. Outside dimensions give the space the object takes up, which is larger.
- US and imperial gallons are different sizes. An imperial gallon is about 20% larger, so the two gallon figures should not be mixed.
Sources
- NASA Glenn Research Center, Volume: volume of a rectangular prism and of a circular cylinder
- NIST, Guide for the Use of the International System of Units (SP 811), Appendix B.8: cubic inch, cubic foot, US gallon and imperial gallon in SI units
