Volume Unit Converter

Capacity, Displacement and the Cube Problem

Volume conversion trips people up for the same reason area conversion does, only worse: the factors are cubed, not squared. A foot is 0.3048 m, so a cubic foot is 0.3048³ = 0.028316846592 m³ — about a thirty-fifth of a cubic metre. Meanwhile the liquid measures (litres, gallons, quarts) live in a parallel vocabulary that has to reconcile with the cubic ones. This converter puts all twelve units on one scale so a tank measured in cubic feet can be quoted in gallons without a two-step detour.

The Formula

Result = Value × (Factor of From-Unit) ÷ (Factor of To-Unit)
(Factors are relative to 1 liter)

The litre is the pivot because it sits neatly between both worlds: 1 L = 1000 cm³ exactly, and 1 m³ = 1000 L exactly. Negative values are rejected before any arithmetic runs.

Cubic Units and Liquid Units on One Scale

All twelve units, in litres and cubic metres
UnitCodeLitersFamily
Millilitersml0.001metric liquid
Cubic Centimeterscm30.001metric cubic
Litersl1metric liquid
Cubic Metersm31000metric cubic
Cubic Inchesin30.016387064imperial cubic
Cubic Feetft328.316846592imperial cubic
US Fluid Ouncesus_floz0.0295735295625US liquid
US Cupsus_cup0.2365882365US liquid
US Pintsus_pint0.473176473US liquid
US Quartsus_qt0.946352946US liquid
US Gallonsus_gal3.785411784US liquid
Imperial Gallonsimp_gal4.54609UK liquid
Note: The US gallon is defined as exactly 231 cubic inches. That's where 3.785411784 L comes from: 231 × 0.016387064 = 3.785411784. The imperial gallon has no such tidy cubic-inch definition — it is simply defined as 4.54609 L.

Cubic Feet to Everything Else

Tank and container capacity usually starts as a cubic measurement. Here is what one cubic foot is worth across the scale:

1 cubic foot expressed in each supported unit
UnitValue
Liters28.316846592
Milliliters / Cubic Centimeters28316.846592
Cubic Meters0.028316846592
US Gallons7.48051948
Imperial Gallons6.22883546
US Quarts29.92207792
Cubic Inches1728

1728 cubic inches per cubic foot is exact — it is 12³. The 7.48051948 US gallons per cubic foot figure is the one used throughout plumbing and pool sizing.

Cubic Metres and Litres

1 cubic metre across the scale
UnitValue
Liters1000
US Gallons264.17205236
Imperial Gallons219.9692483
Cubic Feet35.31466672

Applications

  • Tank and vessel sizing — capacity derived from length × width × height in feet, reported to a client in gallons or litres.
  • Water and irrigation — utility meters commonly register in cubic feet or cubic metres while consumption is discussed in gallons or litres.
  • Freight and shipping — container and pallet cube quoted in cubic metres against cargo specified in cubic feet.
  • Engine and compressor specs — displacement in cubic inches or cc, air delivery in cubic feet per minute.
  • Concrete and aggregate — volumes ordered by the cubic yard or cubic metre against a form measured in cubic feet.

How to Use This Calculator

  1. Compute or read off the volume figure and enter it in the Value field.
  2. Select its current unit in the first dropdown — watch the US-versus-Imperial gallon distinction here.
  3. Select the unit you need in the second dropdown.
  4. Press Calculate. The output shows the result along with both factors and the division, so it can be checked independently.

Related Calculations

For a cooking and fuel-oriented take on the same units, see the Volume Converter. When the container dimensions themselves need converting first, use the Length Converter.