Mass per volume density.
Stones per Gallon to Long tons per Cup Converter — st/gal to long ton/cup
Convert Stone per Gallon (st/gal) to Long ton per Cup (long ton/cup) using the exact conversion factor (1 stone per gallon = 0.000390625 long ton per cup). See the formula, worked examples, and conversion table.
Stones per Gallon to Long tons 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 1677.569982 / 4.29457916e+6.
Density uses kilograms per cubic meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Stones per Gallon to Long tons per Cup
Stone per Gallon and Long ton 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
long tons per cup = stones per gallon × 0.000390625
This factor comes from each unit's defined relationship to the category's base unit: 1 stone per gallon equals 1677.56998244 base units, and 1 long ton per cup equals 4294579.15504 base units, so dividing one by the other gives the direct stone per gallon-to-long ton per cup factor of 0.000390625.
Simple example
1 st/gal × 0.000390625 = 0.000390625 long ton/cup
1 stone per gallon = 0.000390625 long tons per cup.
Real-world example
1,000 st/gal × 0.000390625 = 0.390625 long ton/cup
1,000 stones per gallon = 0.390625 long tons per cup.
Conversion table
| Stone per Gallon (st/gal) | Long ton per Cup (long ton/cup) |
|---|---|
| 0.1 st/gal | 0.0000390625 long ton/cup |
| 1 st/gal | 0.000390625 long ton/cup |
| 10 st/gal | 0.00390625 long ton/cup |
| 100 st/gal | 0.0390625 long ton/cup |
| 1,000 st/gal | 0.390625 long ton/cup |
| 10,000 st/gal | 3.90625 long ton/cup |
Reverse conversion: Long ton per Cup to Stone per Gallon
0.000390625 long ton/cup × 2560 = 1 st/gal
0.000390625 long tons per cup = 1 stones per gallon.
stones per gallon = long tons per cup × 2560
For a page dedicated to this direction, see Long ton per Cup to Stone per Gallon.
Understanding the Stone per Gallon (st/gal)
Mass per volume density.
Understanding the Long ton per Cup (long ton/cup)
Mass per volume density.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many long tons per cup are in 1 stone per gallon?
1 stone per gallon equals 0.000390625 long tons per cup, using the exact defined conversion factor rather than an estimate.
How do I convert stone per gallon to long ton per cup?
Multiply the stone per gallon value by 0.000390625. The converter above does this instantly to whatever precision you set.
How do I convert long ton per cup back to stone per gallon?
Use the reverse factor: 1 long ton per cup equals 2,560 stones per gallon. You can also use the swap control in the converter above to flip the direction instantly.
What is a stone per gallon?
Stone per Gallon (st/gal) is a unit of density.
What is a long ton per cup?
Long ton per Cup (long ton/cup) is a unit of density.
Is the stone per gallon to long ton per cup conversion exact?
Yes. Both stone per gallon and long ton per cup are defined by fixed standards rather than physical artifacts, so the factor of 0.000390625 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.