Mass per volume density.
Ounces per Cubic foot to Grains per Cup Converter — oz/ft3 to gr/cup
Convert Ounce per Cubic foot (oz/ft3) to Grain per Cup (gr/cup) using the exact conversion factor (1 ounce per cubic foot = 3.655327691 grain per cup). See the formula, worked examples, and conversion table.
Ounces per Cubic foot 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 1.001153961 / 0.2738889767.
Density uses kilograms per cubic meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Ounces per Cubic foot to Grains per Cup
Ounce per Cubic foot 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. Both are mass per volume density units.
Formula
grains per cup = ounces per cubic foot × 3.65532769097
This factor comes from each unit's defined relationship to the category's base unit: 1 ounce per cubic foot equals 1.00115396087 base units, and 1 grain per cup equals 0.273888976724 base units, so dividing one by the other gives the direct ounce per cubic foot-to-grain per cup factor of 3.65532769097.
Simple example
1 oz/ft3 × 3.655327691 = 3.655327691 gr/cup
1 ounce per cubic foot = 3.655327691 grains per cup.
Real-world example
1,000 oz/ft3 × 3.655327691 = 3,655.327691 gr/cup
1,000 ounces per cubic foot = 3,655.327691 grains per cup.
Conversion table
| Ounce per Cubic foot (oz/ft3) | Grain per Cup (gr/cup) |
|---|---|
| 0.1 oz/ft3 | 0.3655327691 gr/cup |
| 1 oz/ft3 | 3.655327691 gr/cup |
| 10 oz/ft3 | 36.55327691 gr/cup |
| 100 oz/ft3 | 365.5327691 gr/cup |
| 1,000 oz/ft3 | 3,655.327691 gr/cup |
| 10,000 oz/ft3 | 36,553.27691 gr/cup |
Reverse conversion: Grain per Cup to Ounce per Cubic foot
3.655327691 gr/cup × 0.2735732839 = 1 oz/ft3
3.655327691 grains per cup = 1 ounces per cubic foot.
ounces per cubic foot = grains per cup × 0.273573283859
For a page dedicated to this direction, see Grain per Cup to Ounce per Cubic foot.
Understanding the Ounce per Cubic foot (oz/ft3)
Mass per volume density.
Understanding the Grain per Cup (gr/cup)
Mass per volume density.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many grains per cup are in 1 ounce per cubic foot?
1 ounce per cubic foot equals 3.655327691 grains per cup, using the exact defined conversion factor rather than an estimate.
How do I convert ounce per cubic foot to grain per cup?
Multiply the ounce per cubic foot value by 3.655327691. The converter above does this instantly to whatever precision you set.
How do I convert grain per cup back to ounce per cubic foot?
Use the reverse factor: 1 grain per cup equals 0.2735732839 ounces per cubic foot. You can also use the swap control in the converter above to flip the direction instantly.
What is a ounce per cubic foot?
Ounce per Cubic foot (oz/ft3) is a unit of density.
What is a grain per cup?
Grain per Cup (gr/cup) is a unit of density.
Is the ounce per cubic foot to grain per cup conversion exact?
Yes. Both ounce per cubic foot and grain per cup are defined by fixed standards rather than physical artifacts, so the factor of 3.655327691 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.