Mass per volume density.
Grain per Cubic inches to Pounds per Cup Converter — gr/in3 to lb/cup
Convert Grain per Cubic inch (gr/in3) to Pound per Cup (lb/cup) using the exact conversion factor (1 grain per cubic inch = 0.0020625 pound per cup). See the formula, worked examples, and conversion table.
Grain per Cubic inches to Pounds per Cup 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 3.954272101 / 1917.222837.
Density uses kilograms per cubic meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Grain per Cubic inches to Pounds per Cup
Grain per Cubic inch and Pound per Cup 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
pounds per cup = grain per cubic inches × 0.0020625
This factor comes from each unit's defined relationship to the category's base unit: 1 grain per cubic inch equals 3.95427210146 base units, and 1 pound per cup equals 1917.22283707 base units, so dividing one by the other gives the direct grain per cubic inch-to-pound per cup factor of 0.0020625.
Simple example
1 gr/in3 × 0.0020625 = 0.0020625 lb/cup
1 grain per cubic inch = 0.0020625 pounds per cup.
Real-world example
1,000 gr/in3 × 0.0020625 = 2.0625 lb/cup
1,000 grain per cubic inches = 2.0625 pounds per cup.
Conversion table
| Grain per Cubic inch (gr/in3) | Pound per Cup (lb/cup) |
|---|---|
| 0.1 gr/in3 | 0.00020625 lb/cup |
| 1 gr/in3 | 0.0020625 lb/cup |
| 10 gr/in3 | 0.020625 lb/cup |
| 100 gr/in3 | 0.20625 lb/cup |
| 1,000 gr/in3 | 2.0625 lb/cup |
| 10,000 gr/in3 | 20.625 lb/cup |
Reverse conversion: Pound per Cup to Grain per Cubic inch
0.0020625 lb/cup × 484.8484848 = 1 gr/in3
0.0020625 pounds per cup = 1 grain per cubic inches.
grain per cubic inches = pounds per cup × 484.848484848
For a page dedicated to this direction, see Pound per Cup to Grain per Cubic inch.
Understanding the Grain per Cubic inch (gr/in3)
Mass per volume density.
Understanding the Pound per Cup (lb/cup)
Mass per volume density.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many pounds per cup are in 1 grain per cubic inch?
1 grain per cubic inch equals 0.0020625 pounds per cup, using the exact defined conversion factor rather than an estimate.
How do I convert grain per cubic inch to pound per cup?
Multiply the grain per cubic inch value by 0.0020625. The converter above does this instantly to whatever precision you set.
How do I convert pound per cup back to grain per cubic inch?
Use the reverse factor: 1 pound per cup equals 484.8484848 grain per cubic inches. You can also use the swap control in the converter above to flip the direction instantly.
What is a grain per cubic inch?
Grain per Cubic inch (gr/in3) is a unit of density.
What is a pound per cup?
Pound per Cup (lb/cup) is a unit of density.
Is the grain per cubic inch to pound per cup conversion exact?
Yes. Both grain per cubic inch and pound per cup are defined by fixed standards rather than physical artifacts, so the factor of 0.0020625 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.