Understanding Ounces per Cubic Inch to Pounds per Cubic Inch Conversion
An ounce per cubic inch (oz/in3) expresses density as avoirdupois ounces of mass packed into one cubic inch of volume, while a pound per cubic inch (lb/in3) uses the pound over that same volume. Because there are exactly 16 ounces in a pound, both units share an identical volume basis, so converting between them is a pure mass-unit rescale. Engineers and machinists in the United States often meet these units when comparing the density of metals, plastics, and cast alloys stated on imperial material datasheets.
Conversion Formula
To convert ounces per cubic inch to pounds per cubic inch, multiply by this factor:
Step-by-Step Example
Convert 25 ounces per cubic inch to pounds per cubic inch.
How to Convert Ounces per Cubic Inch to Pounds per Cubic Inch
Because both units use the cubic inch, you only rescale the mass from ounces to pounds.
- Start with your density: Note the value in ounces per cubic inch (oz/in3).
- Apply the factor: Multiply by 0.0625, which is the same as dividing by 16 ounces per pound.
- Read the result: The product is your density in pounds per cubic inch (lb/in3).
- Worked result: 25 oz/in3 × 0.0625 = 1.5625 lb/in3.
ounces per cubic inch to pounds per cubic inch conversion table
| ounces per cubic inch (oz/in3) | pounds per cubic inch (lb/in3) |
|---|---|
| 0 | 0 |
| 1 | 0.0625 |
| 2 | 0.125 |
| 3 | 0.1875 |
| 4 | 0.25 |
| 5 | 0.3125 |
| 6 | 0.375 |
| 7 | 0.4375 |
| 8 | 0.5 |
| 9 | 0.5625 |
| 10 | 0.625 |
| 15 | 0.9375 |
| 20 | 1.25 |
| 25 | 1.5625 |
| 30 | 1.875 |
| 40 | 2.5 |
| 50 | 3.125 |
| 60 | 3.75 |
| 70 | 4.375 |
| 80 | 5 |
| 90 | 5.625 |
| 100 | 6.25 |
| 150 | 9.375 |
| 200 | 12.5 |
| 250 | 15.625 |
| 300 | 18.75 |
| 400 | 25 |
| 500 | 31.25 |
| 600 | 37.5 |
| 700 | 43.75 |
| 800 | 50 |
| 900 | 56.25 |
| 1000 | 62.5 |
| 2000 | 125 |
| 3000 | 187.5 |
| 4000 | 250 |
| 5000 | 312.5 |
| 10000 | 625 |
| 25000 | 1562.5 |
| 50000 | 3125 |
| 100000 | 6250 |
| 250000 | 15625 |
| 500000 | 31250 |
| 1000000 | 62500 |
What is the Ounce per Cubic Inch?
The ounce per cubic inch is a unit of density in the imperial and US customary systems, expressing the mass in avoirdupois ounces contained in one cubic inch of a substance. It is used mainly in engineering and materials work where both mass and volume are stated in customary units.
Definition
One ounce per cubic inch equals the mass of one avoirdupois ounce (28.349523125 g) divided by the volume of one cubic inch (16.387064 cm³).
Because one cubic inch is defined exactly as 16.387064 cm³ and one avoirdupois ounce as exactly 28.349523125 g, the conversion is exact: 1 oz/in³ = 1.72999 g/cm³ = 1729.99 kg/m³. This should not be confused with the fluid-ounce-based densities used for liquids.
Origin and History
The unit derives from the avoirdupois ounce, standardized in England and later fixed to the metric system when the international yard and pound were defined in 1959 (1 pound = 0.45359237 kg exactly, hence 1 ounce = 1/16 pound). Combining this mass with the cubic inch produced a natural density measure for machinists and metallurgists working in inches.
Law and Notable Facts
The ounce per cubic inch is a derived unit with no independent legal definition; it follows automatically from the exact definitions of the avoirdupois ounce and the international inch. Because 1 oz/in³ ≈ 1.73 g/cm³, it produces conveniently sized numbers for dense materials.
Real-World Examples and Conversions
- Water (1.000 g/cm³) is about 0.578 oz/in³.
- Aluminium (2.70 g/cm³) is roughly 1.56 oz/in³.
- Steel (about 7.85 g/cm³) is close to 4.54 oz/in³.
- Lead (11.34 g/cm³) is about 6.55 oz/in³.
What is the Pound per Cubic Inch?
The pound per cubic inch is a US customary and imperial unit of mass density, giving the number of avoirdupois pounds packed into one cubic inch. Because a cubic inch is tiny, this unit yields large numbers and is reserved for very dense materials such as metals.
Definition
One pound per cubic inch equals one avoirdupois pound (0.45359237 kg) in a volume of one cubic inch (1.6387064×10⁻⁵ m³). The result is:
Since an inch is exactly 0.0254 m and a pound exactly 0.45359237 kg, the factor 27679.9047... kg/m³ is exact.
Origin and History
Like other Anglo-American density units, it combines the avoirdupois pound with the cubic inch, a fine-grained volume long used in machining and metalworking. It became a favored unit in metallurgy and mechanical engineering, where compact, high-density samples are measured.
Law and Notable Facts
The defining pound and inch were fixed exactly by the 1959 international yard and pound agreement. A striking fact: one pound per cubic inch is about 27.68 times the density of water, so almost every everyday liquid has a density well below 0.1 lb/in³, making the unit practical mainly for solids and metals.
Real-World Examples and Conversions
Aluminum is about 0.098 lb/in³, steel about 0.284 lb/in³, lead about 0.410 lb/in³, and gold about 0.698 lb/in³. Water is only about 0.0361 lb/in³. To convert to kilograms per cubic meter, multiply by 27679.9; to grams per cubic centimeter, multiply by 27.6799.
Frequently Asked Questions
How many pounds per cubic inch are in one ounce per cubic inch?
One ounce per cubic inch equals exactly 0.0625 lb/in3, since a pound contains 16 ounces and the cubic-inch volume basis is unchanged.
Why is the factor exactly 1/16?
Both densities share the same cubic-inch volume, so only the mass unit changes. As 1 pound = 16 ounces, dividing ounces by 16 gives the equivalent pounds, i.e. multiplying by 0.0625.
How do I convert pounds per cubic inch back to ounces per cubic inch?
Multiply the lb/in3 value by 16. For example, 1.5625 lb/in3 × 16 returns 25 oz/in3.
Where is this conversion used in practice?
It appears when U.S. material datasheets list a metal or polymer density in ounces per cubic inch and a downstream weight or strength calculation needs it in pounds per cubic inch.
What is 10 ounces per cubic inch in pounds per cubic inch?
Multiply 10 by 0.0625 to get 0.625 lb/in3.
People also convert
Complete ounces per cubic inch conversion table
| Unit | Result |
|---|---|
| kilograms per cubic meter (kg/m3) | 1729.994 kg/m3 |
| grams per cubic centimeter (g/cm3) | 1.729994 g/cm3 |
| grams per milliliter (g/mL) | 1.729994 g/mL |
| grams per liter (g/L) | 1729.994 g/L |
| milligrams per milliliter (mg/mL) | 1729.994 mg/mL |
| kilograms per liter (kg/L) | 1.729994 kg/L |
| tonnes per cubic meter (t/m3) | 1.729994 t/m3 |
| pounds per cubic foot (lb/ft3) | 108 lb/ft3 |
| pounds per cubic inch (lb/in3) | 0.0625 lb/in3 |
| pounds per cubic yard (lb/yd3) | 2916 lb/yd3 |
| pounds per US gallon (lb/gal) | 14.4375 lb/gal |
| ounces per US gallon (oz/gal) | 231 oz/gal |
| slugs per cubic foot (slug/ft3) | 3.356743 slug/ft3 |