Mass per volume density.
Grains per Cubic Millimeter to Pounds per Gallon Converter — gr/mm3 to lb/gal
Convert Grain per Cubic Millimeter (gr/mm3) to Pound per Gallon (lb/gal) using the exact conversion factor (1 grain per cubic millimeter = 540.773112 pound per gallon). See the formula, worked examples, conversion table, and common uses.
Grains per Cubic Millimeter to Pounds per Gallon 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 64798.91 / 119.8264273.
Density uses kilograms per cubic meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Grains per Cubic Millimeter to Pounds per Gallon
Grain per Cubic Millimeter and Pound per Gallon 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 gallon = grains per cubic millimeter × 540.773112
This factor comes from each unit's defined relationship to the category's base unit: 1 grain per cubic millimeter equals 64798.91 base units, and 1 pound per gallon equals 119.826427317 base units, so dividing one by the other gives the direct grain per cubic millimeter-to-pound per gallon factor of 540.773112.
Simple example
1 gr/mm3 × 540.773112 = 540.773112 lb/gal
1 grain per cubic millimeter = 540.773112 pounds per gallon.
Real-world example
1,000 gr/mm3 × 540.773112 = 540,773.112 lb/gal
1,000 grains per cubic millimeter = 540,773.112 pounds per gallon.
Conversion table
| Grain per Cubic Millimeter (gr/mm3) | Pound per Gallon (lb/gal) |
|---|---|
| 0.1 gr/mm3 | 54.0773112 lb/gal |
| 1 gr/mm3 | 540.773112 lb/gal |
| 10 gr/mm3 | 5,407.73112 lb/gal |
| 100 gr/mm3 | 54,077.3112 lb/gal |
| 1,000 gr/mm3 | 540,773.112 lb/gal |
| 10,000 gr/mm3 | 5,407,731.12 lb/gal |
Reverse conversion: Pound per Gallon to Grain per Cubic Millimeter
540.773112 lb/gal × 0.001849204367 = 1 gr/mm3
540.773112 pounds per gallon = 1 grains per cubic millimeter.
grains per cubic millimeter = pounds per gallon × 0.00184920436651
For a page dedicated to this direction, see Pound per Gallon to Grain per Cubic Millimeter.
Understanding the Grain per Cubic Millimeter (gr/mm3)
Mass per volume density.
Understanding the Pound per Gallon
Pound per Gallon (lb/gal) measures density. The US customary unit for liquid density, based on the US gallon (231 cubic inches). It is classified as a US customary density unit.
Where it's used: United States (paint, fuel, and industrial liquid density specifications)
lb/gal vs. lb/ft³. Both are US customary density units; they're related through the real, fixed relationship between the US gallon and the cubic foot (1 cubic foot ≈ 7.48 US gallons), not a round conversion factor.
Uses of the Pound per Gallon today
- US paint and coatings density specifications
- US fuel and petroleum liquid density specs
- Industrial liquid handling and shipping weight calculations
Pound per Gallon — sources
- NIST Handbook 44 — General tables of units including US customary density measures.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many pounds per gallon are in 1 grain per cubic millimeter?
1 grain per cubic millimeter equals 540.773112 pounds per gallon, using the exact defined conversion factor rather than an estimate.
How do I convert grain per cubic millimeter to pound per gallon?
Multiply the grain per cubic millimeter value by 540.773112. The converter above does this instantly to whatever precision you set.
How do I convert pound per gallon back to grain per cubic millimeter?
Use the reverse factor: 1 pound per gallon equals 0.0018492044 grains per cubic millimeter. You can also use the swap control in the converter above to flip the direction instantly.
What is a grain per cubic millimeter?
Grain per Cubic Millimeter (gr/mm3) is a unit of density.
What is a pound per gallon?
Pound per Gallon (lb/gal) measures density. The US customary unit for liquid density, based on the US gallon (231 cubic inches). It is classified as a US customary density unit.
Is the grain per cubic millimeter to pound per gallon conversion exact?
Yes. Both grain per cubic millimeter and pound per gallon are defined by fixed standards rather than physical artifacts, so the factor of 540.773112 used above is exact to as many digits as you choose to display.
What is the difference between lb/gal vs. lb/ft³?
Both are US customary density units; they're related through the real, fixed relationship between the US gallon and the cubic foot (1 cubic foot ≈ 7.48 US gallons), not a round conversion factor.