Mass per volume density.
Pounds per Fluid ounce to Grain per Cubic inches Converter — lb/fl oz to gr/in3
Convert Pound per Fluid ounce (lb/fl oz) to Grain per Cubic inch (gr/in3) using the exact conversion factor (1 pound per fluid ounce = 3,878.787879 grain per cubic inch). See the formula, worked examples, and conversion table.
Pounds per Fluid ounce to Grain per Cubic inches converter
Converter
Density Converter
Convert thousands of mass-per-volume density combinations for science, engineering, agriculture, and fluids.
Context values
Some unit families need one extra value for a physically accurate result.
Mass per volume density.
Result = input x 15337.7827 / 3.954272101.
Density uses kilograms per cubic meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Pounds per Fluid ounce to Grain per Cubic inches
Pound per Fluid ounce and Grain per Cubic inch both measure density — mass per unit volume — a property used to identify materials, check manufacturing quality, and predict whether something floats or sinks. As a fixed reference point, water has a density of exactly 1000 kg/m³ (1 g/cm³, 1 g/mL) at its temperature of maximum density, which is why many density figures in science and engineering are quoted relative to water. Both are mass per volume density units.
Formula
grain per cubic inches = pounds per fluid ounce × 3878.78787879
This factor comes from each unit's defined relationship to the category's base unit: 1 pound per fluid ounce equals 15337.7826966 base units, and 1 grain per cubic inch equals 3.95427210146 base units, so dividing one by the other gives the direct pound per fluid ounce-to-grain per cubic inch factor of 3878.78787879.
Simple example
1 lb/fl oz × 3878.787879 = 3,878.787879 gr/in3
1 pound per fluid ounce = 3,878.787879 grain per cubic inches.
Real-world example
1,000 lb/fl oz × 3878.787879 = 3,878,787.879 gr/in3
1,000 pounds per fluid ounce = 3,878,787.879 grain per cubic inches.
Conversion table
| Pound per Fluid ounce (lb/fl oz) | Grain per Cubic inch (gr/in3) |
|---|---|
| 0.1 lb/fl oz | 387.8787879 gr/in3 |
| 1 lb/fl oz | 3,878.787879 gr/in3 |
| 10 lb/fl oz | 38,787.87879 gr/in3 |
| 100 lb/fl oz | 387,878.7879 gr/in3 |
| 1,000 lb/fl oz | 3,878,787.879 gr/in3 |
| 10,000 lb/fl oz | 38,787,878.79 gr/in3 |
Reverse conversion: Grain per Cubic inch to Pound per Fluid ounce
1 gr/in3 × 0.0002578125 = 0.0002578125 lb/fl oz
1 grain per cubic inch = 0.0002578125 pounds per fluid ounce.
pounds per fluid ounce = grain per cubic inches × 0.0002578125
For a page dedicated to this direction, see Grain per Cubic inch to Pound per Fluid ounce.
Understanding the Pound per Fluid ounce (lb/fl oz)
Mass per volume density.
Understanding the Grain per Cubic inch (gr/in3)
Mass per volume density.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many grain per cubic inches are in 1 pound per fluid ounce?
1 pound per fluid ounce equals 3,878.787879 grain per cubic inches, using the exact defined conversion factor rather than an estimate.
How do I convert pound per fluid ounce to grain per cubic inch?
Multiply the pound per fluid ounce value by 3878.787879. The converter above does this instantly to whatever precision you set.
How do I convert grain per cubic inch back to pound per fluid ounce?
Use the reverse factor: 1 grain per cubic inch equals 0.0002578125 pounds per fluid ounce. You can also use the swap control in the converter above to flip the direction instantly.
What is a pound per fluid ounce?
Pound per Fluid ounce (lb/fl oz) is a unit of density.
What is a grain per cubic inch?
Grain per Cubic inch (gr/in3) is a unit of density.
Is the pound per fluid ounce to grain per cubic inch conversion exact?
Yes. Both pound per fluid ounce and grain per cubic inch are defined by fixed standards rather than physical artifacts, so the factor of 3878.787879 used above is exact to as many digits as you choose to display.
What's the difference between density and mass concentration?
Density is the mass of a pure substance or material per unit volume. Mass concentration is the mass of one component — like a dissolved solute — within a mixture's total volume. The two use the same kind of units but describe different physical situations.