Box Volume Calculator
What a Box Can Actually Hold
A box's stated dimensions tell you its footprint, but not how much it can carry — and that distinction matters whether you're comparing packing box sizes, checking a container against a carrier's volumetric limit, or estimating how much loose fill or liquid a container could hold. This calculator converts three dimensions into a full set of volume units at once, so the figure is ready for whatever comparison you need it for.
The Formula
The calculator accepts inches, feet, centimeters, or meters, converts everything to a common unit internally, then reports the result back out in cubic feet, cubic centimeters, liters, and gallons (as a liquid-capacity equivalent) simultaneously.
Where This Calculation Matters
- Choosing a moving or shipping box — comparing volume in cubic feet is a faster way to judge box capacity than comparing three separate dimensions.
- Estimating packing material needs — volume in liters or gallons helps estimate how much loose-fill packing peanuts or foam a box will require.
- Aquarium and container sizing — the gallon-equivalent output is useful any time a rectangular container's liquid capacity needs a quick estimate.
- Freight and storage quoting — cubic feet is the standard unit movers and self-storage companies use to size a job or a unit.
| Box size (L × W × H, inches) | Cubic feet | Liters | Gallons |
|---|---|---|---|
| Small: 12 × 12 × 12 | 1.00 | 28.3 | 7.48 |
| Medium: 18 × 18 × 16 | 3.00 | 85.0 | 22.44 |
| Large: 24 × 18 × 18 | 4.50 | 127.4 | 33.66 |
| Extra-large: 24 × 24 × 24 | 8.00 | 226.5 | 59.84 |
Computed directly from the formula above; a standard 12" moving box is exactly 1 cubic foot, which is a handy mental benchmark.
How to Use This Calculator
- Enter the length, width, and height of the box.
- Select the unit of measurement — inches, feet, centimeters, or meters.
- Select Calculate to get volume in cubic feet, cubic centimeters, liters, and gallons.
Related Calculations
For larger spaces measured in feet or yards, use the Cubic Feet Calculator, or size a shipping box around a specific item with the Shipping Box Size Calculator.