Mass per volume density.
Pound per Cubic inches to Stones per Cup Converter — lb/in3 to st/cup
Convert Pound per Cubic inch (lb/in3) to Stone per Cup (st/cup) using the exact conversion factor (1 pound per cubic inch = 1.03125 stone per cup). See the formula, worked examples, conversion table, and common uses.
Pound per Cubic inches to Stones 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 / 26841.11972.
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 Stones per Cup
Pound per Cubic inch and Stone 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
stones per cup = pound per cubic inches × 1.03125
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 stone per cup equals 26841.119719 base units, so dividing one by the other gives the direct pound per cubic inch-to-stone per cup factor of 1.03125.
Simple example
1 lb/in3 × 1.03125 = 1.03125 st/cup
1 pound per cubic inch = 1.03125 stones per cup.
Real-world example
1,000 lb/in3 × 1.03125 = 1,031.25 st/cup
1,000 pound per cubic inches = 1,031.25 stones per cup.
Conversion table
| Pound per Cubic inch (lb/in3) | Stone per Cup (st/cup) |
|---|---|
| 0.1 lb/in3 | 0.103125 st/cup |
| 1 lb/in3 | 1.03125 st/cup |
| 10 lb/in3 | 10.3125 st/cup |
| 100 lb/in3 | 103.125 st/cup |
| 1,000 lb/in3 | 1,031.25 st/cup |
| 10,000 lb/in3 | 10,312.5 st/cup |
Reverse conversion: Stone per Cup to Pound per Cubic inch
1.03125 st/cup × 0.9696969697 = 1 lb/in3
1.03125 stones per cup = 1 pound per cubic inches.
pound per cubic inches = stones per cup × 0.969696969697
For a page dedicated to this direction, see Stone 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 Stone per Cup (st/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 stones per cup are in 1 pound per cubic inch?
1 pound per cubic inch equals 1.03125 stones per cup, using the exact defined conversion factor rather than an estimate.
How do I convert pound per cubic inch to stone per cup?
Multiply the pound per cubic inch value by 1.03125. The converter above does this instantly to whatever precision you set.
How do I convert stone per cup back to pound per cubic inch?
Use the reverse factor: 1 stone per cup equals 0.9696969697 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 stone per cup?
Stone per Cup (st/cup) is a unit of density.
Is the pound per cubic inch to stone per cup conversion exact?
Yes. Both pound per cubic inch and stone per cup are defined by fixed standards rather than physical artifacts, so the factor of 1.03125 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.