Soil Porosity Calculator
Calculate soil porosity and void ratio from bulk density and particle density using this free geotechnical calculator in your browser.
Enter Values
Minimum 0
Minimum 0
Before you rely on this: First-pass guide only. Verify safety-critical or regulated work against the relevant standards, your project requirements and a qualified professional.
How to use this calculator
- Enter the void (pore) volume and the total volume.
- Read the porosity and void ratio.
How it works
Porosity = void volume ÷ total volume × 100; void ratio = voids ÷ solids.
Worked example
30 of 100. Porosity 30%, void ratio 0.43.
Common mistakes
- Mixing units between void and total volume.
- Confusing porosity (of total) with void ratio (of solids).
Frequently asked questions
What's the difference between porosity and void ratio?
Porosity is voids as a fraction of total volume; void ratio is voids divided by the solids volume.
Related tools
- Soakwell Volume Calculator
- Degree of Saturation Calculator
- Void Ratio Calculator
- Bulk Density Calculator
- Pore Pressure Ratio Calculator
- Core Recovery Calculator
Explore more in Geology, Geotechnical & Ground Engineering.
Cite this tool
Zerdly. (2026). Soil Porosity Calculator. Retrieved from https://www.zerdly.com/tools/soil-porosity-calculator/
Tip: Enter any known values to calculate the remaining results.
All calculations run in your browser. Your inputs are never saved or transmitted.