Mass per volume density.
Pounds per Fluid ounce to Ounces per Cup Converter — lb/fl oz to oz/cup
Convert Pound per Fluid ounce (lb/fl oz) to Ounce per Cup (oz/cup) using the exact conversion factor (1 pound per fluid ounce = 128 ounce per cup). See the formula, worked examples, and conversion table.
Pounds per Fluid ounce to Ounces 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 15337.7827 / 119.8264273.
Density uses kilograms per cubic meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Pounds per Fluid ounce to Ounces per Cup
Pound per Fluid ounce and Ounce 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
ounces per cup = pounds per fluid ounce × 128
This factor comes from each unit's defined relationship to the category's base unit: 1 pound per fluid ounce equals 15337.7826966 base units, and 1 ounce per cup equals 119.826427317 base units, so dividing one by the other gives the direct pound per fluid ounce-to-ounce per cup factor of 128.
Simple example
1 lb/fl oz × 128 = 128 oz/cup
1 pound per fluid ounce = 128 ounces per cup.
Real-world example
1,000 lb/fl oz × 128 = 128,000 oz/cup
1,000 pounds per fluid ounce = 128,000 ounces per cup.
Conversion table
| Pound per Fluid ounce (lb/fl oz) | Ounce per Cup (oz/cup) |
|---|---|
| 0.1 lb/fl oz | 12.8 oz/cup |
| 1 lb/fl oz | 128 oz/cup |
| 10 lb/fl oz | 1,280 oz/cup |
| 100 lb/fl oz | 12,800 oz/cup |
| 1,000 lb/fl oz | 128,000 oz/cup |
| 10,000 lb/fl oz | 1,280,000 oz/cup |
Reverse conversion: Ounce per Cup to Pound per Fluid ounce
128 oz/cup × 0.0078125 = 1 lb/fl oz
128 ounces per cup = 1 pound per fluid ounce.
pounds per fluid ounce = ounces per cup × 0.0078125
For a page dedicated to this direction, see Ounce per Cup to Pound per Fluid ounce.
Understanding the Pound per Fluid ounce (lb/fl oz)
Mass per volume density.
Understanding the Ounce per Cup (oz/cup)
Mass per volume density.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many ounces per cup are in 1 pound per fluid ounce?
1 pound per fluid ounce equals 128 ounces per cup, using the exact defined conversion factor rather than an estimate.
How do I convert pound per fluid ounce to ounce per cup?
Multiply the pound per fluid ounce value by 128. The converter above does this instantly to whatever precision you set.
How do I convert ounce per cup back to pound per fluid ounce?
Use the reverse factor: 1 ounce per cup equals 0.0078125 pounds per fluid ounce. You can also use the swap control in the converter above to flip the direction instantly.
What is a pound per fluid ounce?
Pound per Fluid ounce (lb/fl oz) is a unit of density.
What is a ounce per cup?
Ounce per Cup (oz/cup) is a unit of density.
Is the pound per fluid ounce to ounce per cup conversion exact?
Yes. Both pound per fluid ounce and ounce per cup are defined by fixed standards rather than physical artifacts, so the factor of 128 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.