This converter turns pounds per cubic foot into pounds per cubic inch instantly, using the exact factor 1 pound per cubic foot = 0.0005787037037 pounds per cubic inch. Type any number and the result updates as you go — nothing is sent to a server, so the arithmetic happens entirely in your browser.
The US construction unit for concrete, soil and timber density. Used for metals and dense engineering materials.
Because the relationship is a simple proportion, one multiplication does the whole job. The table further down gives pre-computed values for the amounts people look up most often, and the result panel also reports the reverse conversion so you can check the figure both ways.
The formula
pounds per cubic foot- The amount you are converting, measured in pounds per cubic foot
0.0005787037037- The exact number of pounds per cubic inch in one pound per cubic foot
pounds per cubic inch- The converted result
How it works, step by step
- Enter the number of pounds per cubic foot you want to convert.
- The value is multiplied by 0.0005787037037, the exact conversion factor.
- The result is displayed in pounds per cubic inch, rounded for readability.
- The unrounded value and the reverse conversion appear underneath so you can verify it.
Worked examples
Converting 5 pounds per cubic foot
Multiply 5 by 0.0005787037. That gives 0.002894 pounds per cubic inch. A quick sanity check: one pound per cubic foot is smaller than one pound per cubic inch, so the number should get smaller — and it does.
Converting 72 pounds per cubic foot
72 × 0.0005787037 = 0.041667 pounds per cubic inch. Working backwards, 0.041667 ÷ 0.0005787037 returns 72 pounds per cubic foot, which confirms the factor is applied the right way round.
How to read your score
Frequently asked questions
How many pounds per cubic inch are in one pound per cubic foot?
Exactly 0.0005787037037. Every conversion on this page is that single number multiplied by your input, so the result carries no rounding error beyond what is shown.
What is the formula to convert pounds per cubic foot to pounds per cubic inch?
Pounds Per Cubic Inch = pounds per cubic foot × 0.0005787037037. To reverse it, divide instead: pounds per cubic foot = pounds per cubic inch ÷ 0.0005787037037, which is the same as multiplying by 1728.
Is the pound per cubic foot bigger than the pound per cubic inch?
No. One pound per cubic foot is only 0.000578704 of a pound per cubic inch, so the pound per cubic inch is the larger unit.
Why does my answer differ slightly from other lb-ft3 to lb-in3 converters?
Most differences come from rounding the factor too early. This tool keeps full double precision through the calculation and only rounds at the final display step, and it also shows the unrounded value so you can see exactly where any difference appears.
What is a pound per cubic foot?
The US construction unit for concrete, soil and timber density.
What is a pound per cubic inch?
Used for metals and dense engineering materials.
Pounds Per Cubic Foot to pounds per cubic inch reference table
| Pounds Per Cubic Foot | Pounds Per Cubic Inch |
|---|---|
| 0.5 lb/ft³ | 0.000289 lb/in³ |
| 1 lb/ft³ | 0.000579 lb/in³ |
| 2 lb/ft³ | 0.001157 lb/in³ |
| 3 lb/ft³ | 0.001736 lb/in³ |
| 5 lb/ft³ | 0.002894 lb/in³ |
| 10 lb/ft³ | 0.005787 lb/in³ |
| 15 lb/ft³ | 0.008681 lb/in³ |
| 20 lb/ft³ | 0.011574 lb/in³ |
| 25 lb/ft³ | 0.014468 lb/in³ |
| 50 lb/ft³ | 0.028935 lb/in³ |
| 75 lb/ft³ | 0.043403 lb/in³ |
| 100 lb/ft³ | 0.05787 lb/in³ |
| 250 lb/ft³ | 0.144676 lb/in³ |
| 500 lb/ft³ | 0.289352 lb/in³ |
| 1000 lb/ft³ | 0.578704 lb/in³ |
Exact factor: 1 pound per cubic foot = 0.0005787037037 pounds per cubic inch. Values rounded for display.