Mass per volume density.
Pound per Cubic inches to Grains per Cup Converter — lb/in3 to gr/cup
Convert Pound per Cubic inch (lb/in3) to Grain per Cup (gr/cup) using the exact conversion factor (1 pound per cubic inch = 101,062.5 grain per cup). See the formula, worked examples, conversion table, and common uses.
Pound per Cubic inches to Grains 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 27679.90471 / 0.2738889767.
Density uses kilograms per cubic meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Pound per Cubic inches to Grains per Cup
Pound per Cubic inch and Grain 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. Pound per Cubic inch is most often used for used in machining and materials engineering, particularly for describing the density of metals, where a smaller volume unit than the cubic foot gives a more convenient figure.
Formula
grains per cup = pound per cubic inches × 101062.5
This factor comes from each unit's defined relationship to the category's base unit: 1 pound per cubic inch equals 27679.9047102 base units, and 1 grain per cup equals 0.273888976724 base units, so dividing one by the other gives the direct pound per cubic inch-to-grain per cup factor of 101062.5.
Simple example
1 lb/in3 × 101062.5 = 101,062.5 gr/cup
1 pound per cubic inch = 101,062.5 grains per cup.
Real-world example
1,000 lb/in3 × 101062.5 = 101,062,500 gr/cup
1,000 pound per cubic inches = 101,062,500 grains per cup.
Conversion table
| Pound per Cubic inch (lb/in3) | Grain per Cup (gr/cup) |
|---|---|
| 0.1 lb/in3 | 10,106.25 gr/cup |
| 1 lb/in3 | 101,062.5 gr/cup |
| 10 lb/in3 | 1,010,625 gr/cup |
| 100 lb/in3 | 10,106,250 gr/cup |
| 1,000 lb/in3 | 101,062,500 gr/cup |
| 10,000 lb/in3 | 1,010,625,000 gr/cup |
Reverse conversion: Grain per Cup to Pound per Cubic inch
1 gr/cup × 0.000009894867038 = 0.0000098949 lb/in3
1 grain per cup = 0.0000098949 pound per cubic inches.
pound per cubic inches = grains per cup × 0.00000989486703772
For a page dedicated to this direction, see Grain per Cup to Pound per Cubic inch.
Understanding the Pound per Cubic inch
Pound per Cubic inch (lb/in3) measures density. A US customary density unit suited to describing dense materials in a small volume. It is classified as a US customary density unit.
Where it's used: United States
Uses of the Pound per Cubic inch today
- Used in machining and materials engineering, particularly for describing the density of metals, where a smaller volume unit than the cubic foot gives a more convenient figure
Understanding the Grain per Cup (gr/cup)
Mass per volume density.
Pound per Cubic inch — sources
- US materials-engineering reference tables — Pounds per cubic inch is a commonly tabulated density unit for metals in US machining and materials references.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many grains per cup are in 1 pound per cubic inch?
1 pound per cubic inch equals 101,062.5 grains per cup, using the exact defined conversion factor rather than an estimate.
How do I convert pound per cubic inch to grain per cup?
Multiply the pound per cubic inch value by 101062.5. The converter above does this instantly to whatever precision you set.
How do I convert grain per cup back to pound per cubic inch?
Use the reverse factor: 1 grain per cup equals 0.0000098949 pound per cubic inches. You can also use the swap control in the converter above to flip the direction instantly.
What is a pound per cubic inch?
Pound per Cubic inch (lb/in3) measures density. A US customary density unit suited to describing dense materials in a small volume. It is classified as a US customary density unit.
What is a grain per cup?
Grain per Cup (gr/cup) is a unit of density.
Is the pound per cubic inch to grain per cup conversion exact?
Yes. Both pound per cubic inch and grain per cup are defined by fixed standards rather than physical artifacts, so the factor of 101062.5 used above is exact to as many digits as you choose to display.
Where is the pound per cubic inch still used today?
United States
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.