Calculate Hausner ratio, tapped density, or bulk density from any 2 inputs with unit conversion for lb/ft³, kg/m³, and g/cm³, and view steps.
Related Calculators
- Glass Transition Temperature Calculator
- Agitator Tip Speed Calculator
- Hydrometer Correction Calculator
- Lever Rule Calculator
- All Chemistry Calculators
Hausner Ratio Formula
The Hausner ratio compares tapped density to bulk density. It is a dimensionless value, so the tapped density and bulk density must be in compatible units before dividing.
HR = rho_t / rho_b
rho_t = HR * rho_b
rho_b = rho_t / HR
- HR = Hausner ratio
- rho_t = tapped density
- rho_b = bulk density
The calculator can solve for any one missing value when you enter the other two:
- Hausner ratio: divides tapped density by bulk density.
- Tapped density: multiplies Hausner ratio by bulk density.
- Bulk density: divides tapped density by Hausner ratio.
If the density units are different, the calculator converts them to a common density unit before applying the formula.
Hausner Ratio Interpretation
Lower Hausner ratios usually indicate better powder flow. Higher values indicate that the material compresses more when tapped, which often means poorer flowability.
| Hausner Ratio | Typical Flow Character |
|---|---|
| 1.00 to 1.11 | Excellent |
| 1.12 to 1.18 | Good |
| 1.19 to 1.25 | Fair |
| 1.26 to 1.34 | Passable |
| 1.35 to 1.45 | Poor |
| 1.46 to 1.59 | Very poor |
| 1.60 and above | Extremely poor |
Density Unit Conversions Used
| Unit | Equivalent in lb/ft³ |
|---|---|
| 1 lb/ft³ | 1 lb/ft³ |
| 1 kg/m³ | 0.062428 lb/ft³ |
| 1 g/cm³ | 62.428 lb/ft³ |
Example Calculations
Example 1: Calculate Hausner ratio
You have a tapped density of 0.72 g/cm³ and a bulk density of 0.60 g/cm³.
HR = 0.72 / 0.60 = 1.20
The Hausner ratio is 1.20, which is typically considered fair flow.
Example 2: Calculate bulk density
You have a Hausner ratio of 1.25 and a tapped density of 750 kg/m³.
rho_b = 750 / 1.25 = 600 kg/m^3
The bulk density is 600 kg/m³.
FAQ
What does the Hausner ratio measure?
The Hausner ratio measures how much a powder or granular material compacts when tapped. It compares tapped density to bulk density. A value close to 1 means the material does not compact much, which usually indicates better flow.
Does the Hausner ratio have units?
No. The Hausner ratio is unitless because it is a density divided by another density. The density units cancel out, but both densities must describe the same material and must be converted to compatible units before calculation.
Can the Hausner ratio be less than 1?
In normal use, the Hausner ratio should not be less than 1 because tapped density is usually greater than or equal to bulk density. A value below 1 usually means the densities were entered in the wrong order, measured incorrectly, or not converted consistently.