Cubic Feet to Cubic Inches Converter (ft³ to in³)

Calculate cubic inches from cubic feet instantly, or convert cubic inches back to cubic feet, using the 1,728 conversion factor.

Cubic Feet to Cubic Inches Formula

To convert a volume, use the mode that matches what you have. If you already know the volume, convert directly:

CI = CF * 1728

CF = CI / 1728

If you only have the dimensions of a box or space, find the volume first, then convert:

CI = L * W * H

CI = volume in cubic inches
CF = volume in cubic feet
L, W, H = length, width, and height, all measured in inches
1728 = the number of cubic inches in one cubic foot (12 x 12 x 12)

One cubic foot is a cube that measures 1 foot on every side. Since 1 foot equals 12 inches, that same cube measures 12 inches on every side, so it holds 12 * 12 * 12 = 1728 cubic inches. That is why you multiply cubic feet by 1728 to get cubic inches, and divide cubic inches by 1728 to get cubic feet. When you work from raw dimensions, multiply length by width by height first; if those dimensions are in feet the result is in cubic feet, and if they are in inches the result is in cubic inches.

Common Cubic Feet to Cubic Inches Conversions

Use this table for quick reference. Each cubic foot value is multiplied by 1728.

Cubic Feet (ft³)	Cubic Inches (in³)
0.5	864
1	1,728
2	3,456
3	5,184
5	8,640
10	17,280
25	43,200
100	172,800

To go the other way, divide the cubic inches by 1728. For example, 3,456 cubic inches divided by 1728 equals 2 cubic feet.

Example Problems

Example 1. You have a storage box with a volume of 4 cubic feet and want the value in cubic inches. Multiply by 1728: 4 * 1728 = 6,912 cubic inches.

Example 2. A shipping carton measures 18 inches long, 12 inches wide, and 10 inches high. Multiply the dimensions to get the volume in cubic inches: 18 * 12 * 10 = 2,160 cubic inches. To express that in cubic feet, divide by 1728: 2,160 / 1728 = 1.25 cubic feet.

FAQ

How many cubic inches are in a cubic foot?
There are 1,728 cubic inches in one cubic foot. This comes from cubing the 12 inches in a foot: 12 x 12 x 12 = 1,728.

How do you convert cubic inches back to cubic feet?
Divide the number of cubic inches by 1,728. For instance, 5,184 cubic inches divided by 1,728 gives 3 cubic feet.

Do I need to convert my dimensions to inches before multiplying?
Only if you want the answer in cubic inches and your measurements are in feet. If you multiply length, width, and height that are all in inches, you already get cubic inches. If they are all in feet, you get cubic feet, which you then multiply by 1,728 to reach cubic inches.

Cubic Feet To Cubic Inches Converter Calculator