Use this geological calculation for a transparent first-pass interpretation of measured rock, soil, fluid, well, stratigraphic, isotopic, geophysical, or seismic data under an explicitly selected model.

Bulk density

Dry bulk density of the sample in kg/m3.

Grain density

Grain (solid particle) density in kg/m3.

Compute porosity as n = 1 - (bulk density / grain density) for a rock or soil sample. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Porosity fraction

Porosity as a fraction (dimensionless).

Porosity percent

Porosity expressed in percent.

• Geotechnical correlations and idealized failure models depend on stratigraphy, sampling disturbance, drainage, stress history, groundwater, density, anisotropy, scale, construction sequence, and laboratory or field method. Site-specific design requires investigation and code factors.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Compare independent measurements and models, retain units and analytical metadata, propagate uncertainty, and validate interpretations against logs, cores, maps, laboratory data, or field observations.

• Bulk Density From Porosity Calculator

  Compute dry bulk density as the product of grain density and (1 - porosity).

• Rock Porosity Calculator

  Compute the porosity fraction and percentage of a rock sample from its pore volume and bulk volume.

• Buoyant Density Calculator

  Compute the buoyant (submerged) density of a saturated soil or rock as saturated density minus water density.