Convert Cubic Feet to Cubic Inches Instantly
Use this Cubic Feet to Cubic Inches converter to change volume from ft³ into in³ with exact arithmetic. Enter any whole or decimal cubic-foot value, reverse the conversion from cubic inches, calculate a rectangular box, or compare the same volume across several common units.
Convert ft³ to in³, reverse in³ to ft³, calculate a box volume, or compare one volume across cubic feet, cubic inches, cubic yards, liters and cubic meters.
Enter cubic feet to calculate the exact equivalent in cubic inches and useful related volume units.
Decimals such as 0.25, 1.5 and 12.75 are supported.
Reverse the conversion by dividing cubic inches by 1,728.
Enter length, width and height in inches or feet to calculate cubic inches and cubic feet.
Enter one volume and choose its starting unit to convert it into ft³, in³, yd³, liters and m³.
Cubic feet and cubic inches both measure three-dimensional volume. The difference is scale. A cubic foot is the volume of a cube that is one foot long, one foot wide and one foot high. A cubic inch is the volume of a cube that measures one inch on each side.
Because one foot contains exactly 12 inches, each dimension of a one-cubic-foot cube contains 12 inch-lengths. Volume uses three dimensions, so the conversion factor is 12 × 12 × 12, which equals 1,728. Therefore, 1 cubic foot equals exactly 1,728 cubic inches.
Example: 2.5 ft³ × 1,728 = 4,320 in³.
Example: 3,456 in³ ÷ 1,728 = 2 ft³.
The foot-to-inch relationship is exact, so the cubic-foot-to-cubic-inch relationship is exact as well. Metric equivalents shown on this page are based on the exact international definition of the foot as 0.3048 meter.
For official measurement guidance, see the NIST SI Units – Length guidance and NIST conversion factors.
Use this table for quick reference. Every in³ value is obtained by multiplying cubic feet by 1,728. The additional columns help compare the same physical volume in cubic yards and liters.
| Cubic Feet | Cubic Inches | Cubic Yards | Liters |
|---|---|---|---|
| 0.01 ft³ | 17.280000 in³ | 0.00037037 yd³ | 0.283168 L |
| 0.05 ft³ | 86.400000 in³ | 0.00185185 yd³ | 1.415842 L |
| 0.1 ft³ | 172.800000 in³ | 0.00370370 yd³ | 2.831685 L |
| 0.25 ft³ | 432.000000 in³ | 0.00925926 yd³ | 7.079212 L |
| 0.5 ft³ | 864.000000 in³ | 0.01851852 yd³ | 14.158423 L |
| 0.75 ft³ | 1,296.000000 in³ | 0.02777778 yd³ | 21.237635 L |
| 1 ft³ | 1,728.000000 in³ | 0.03703704 yd³ | 28.316847 L |
| 1.5 ft³ | 2,592.000000 in³ | 0.05555556 yd³ | 42.475270 L |
| 2 ft³ | 3,456.000000 in³ | 0.07407407 yd³ | 56.633693 L |
| 3 ft³ | 5,184.000000 in³ | 0.11111111 yd³ | 84.950540 L |
| 5 ft³ | 8,640.000000 in³ | 0.18518519 yd³ | 141.584233 L |
| 10 ft³ | 17,280.000000 in³ | 0.37037037 yd³ | 283.168466 L |
| 20 ft³ | 34,560.000000 in³ | 0.74074074 yd³ | 566.336932 L |
| 50 ft³ | 86,400.000000 in³ | 1.85185185 yd³ | 1,415.842330 L |
| 100 ft³ | 172,800.000000 in³ | 3.70370370 yd³ | 2,831.684659 L |
0.25 × 1,728 = 432 in³.
0.5 × 1,728 = 864 in³.
1.5 × 1,728 = 2,592 in³.
3 × 1,728 = 5,184 in³.
The same method works for any decimal value. For example, 0.37 ft³ × 1,728 = 639.36 in³. Keeping the calculation unrounded until the final result is especially useful when working with measured container dimensions or engineering specifications.
A common mistake is to use 12 as the conversion factor simply because one foot equals 12 inches. That works for length, but not for volume. A cubic unit expands in three directions: length, width and height.
This is also why square-foot conversions use 12² = 144, while cubic-foot conversions use 12³ = 1,728. Understanding the exponent prevents unit mistakes when moving among length, area and volume measurements.
A 12-inch by 12-inch by 12-inch cube occupies exactly one cubic foot.
Converting cubic feet to cubic inches is useful when a larger container or space is described in ft³ but a component, package, cavity or product specification is given in in³. Common examples include shipping cartons, storage bins, appliance compartments, air spaces, equipment housings, woodworking projects, cabinetry, small tanks and dimensional packaging.
For example, a storage compartment with a capacity of 2 ft³ contains 3,456 in³. A box listed as 0.75 ft³ contains 1,296 in³. Converting both values into the same unit makes it easier to compare items when manufacturers or plans use different volume units.
A cubic foot is a larger customary volume unit based on a cube measuring one foot on each side. A cubic inch is much smaller and represents a cube one inch on each side. Both measure volume, not area or length.
The units are related through the linear foot-to-inch conversion. Since a foot is 12 inches, the three-dimensional volume relationship is 12³. This is the key reason the conversion factor is 1,728 rather than 12 or 144.
If you know a box's internal length, width and height in inches, multiply those three numbers directly to get cubic inches. A box measuring 24 in × 18 in × 12 in has a volume of 5,184 in³. Dividing 5,184 by 1,728 gives 3 ft³.
If the dimensions are in feet, multiply length × width × height to obtain cubic feet first, then multiply the result by 1,728. The third calculator above automates both approaches and is useful for cartons, cabinets, bins and rectangular storage spaces.
Decimal cubic feet convert with the same exact factor. A quarter cubic foot is 432 in³, half a cubic foot is 864 in³, and three-quarters of a cubic foot is 1,296 in³. Values such as 1.25 ft³, 2.6 ft³ or 12.75 ft³ do not require a different formula.
If your source measurement is a fraction, convert the fraction to a decimal or calculate the fraction of 1,728. For example, one eighth of a cubic foot is 1,728 ÷ 8 = 216 in³.
For larger material quantities, cubic yards may be more convenient. One cubic yard contains exactly 27 cubic feet because a yard is 3 feet and 3³ = 27. For metric work, one cubic foot equals exactly 0.028316846592 cubic meter and therefore 28.316846592 liters.
If you need related conversions, see our Liters to Cubic Yards, Milliliters to Cubic Inches, Cubic Centimeters to Cubic Inches, Liters to Cubic Meters, and Cubic Inches to Cubic Feet tools.
That converts feet to inches for length, not ft³ to in³ for volume.
144 is the square-foot-to-square-inch area factor, not the cubic-volume factor.
Convert all length dimensions to the same unit before multiplying length × width × height.
Keep full precision through intermediate calculations and round only the displayed answer.
The ft³-to-in³ conversion is exact because the international foot is defined exactly in meters and the foot-to-inch relationship is exactly 12 inches per foot. For authoritative unit guidance, consult NIST's SI Units – Length material and the NIST Guide to SI conversion factors.
For most practical projects, showing two to six decimal places is more than sufficient. However, if the original measurements are approximate, displaying many extra digits does not make the underlying measurement more accurate.
Quick answers about ft³, in³ and volume conversion.