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Degree of Saturation Calculator

Calculate degree saturation with our free science calculator. Uses standard scientific formulas with unit conversions and explanations.

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Earth Science & Geology

Degree of Saturation Calculator

Calculate the degree of saturation, porosity, and unit weights of soil from water content, specific gravity, and void ratio or bulk density.

Last updated: December 2025Reviewed by NovaCalculator Mathematics Team

Calculator

Adjust values & calculate

66.3%

Degree of Saturation

0.720

Void Ratio (e)

41.9%

Porosity (n)

27.7%

Vol. Water

14.1%

Vol. Air

15.11

Dry Unit Wt (kN/m3)

17.83

Bulk Unit Wt (kN/m3)

19.22

Sat. Unit Wt (kN/m3)

9.41

Submerged Wt (kN/m3)

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Formula

S = (w * Gs) / e; n = e / (1 + e)

This Degree of Saturation Calculator computes results from your provided inputs using the calculator's underlying model.

Last reviewed: December 2025

Expert Insights

Background & Theory

The Degree of Saturation Calculator applies the following established principles and formulas. Earth science calculators draw on a wide range of measurement scales and physical principles that quantify natural phenomena across geological, atmospheric, and hydrological systems. Earthquake magnitude is most precisely described by the Moment Magnitude Scale (Mw), which replaced the original Richter scale for larger events. Mw is calculated as Mw = (2/3) log10(M0) โˆ’ 10.7, where M0 is the seismic moment in dyne-centimeters. The Richter scale, while still referenced colloquially, is a local magnitude (ML) measurement derived from peak seismograph amplitude at a standard 100 km distance. Wind intensity is classified using the Beaufort Scale, a 13-point empirical scale (0โ€“12) relating wind speed in knots to observable sea and land effects, with Beaufort 12 corresponding to hurricane-force winds above 64 knots. Tropical cyclone intensity is further categorized by the Saffir-Simpson Hurricane Wind Scale, which assigns Categories 1 through 5 based on sustained wind speed, correlating with expected structural damage. Mineral hardness is quantified on the Mohs scale (1โ€“10), comparing scratch resistance relative to reference minerals from talc (1) to diamond (10). Soil composition analysis measures the proportions of sand, silt, and clay by particle size, alongside organic matter content, bulk density, and porosity, which together determine engineering and agricultural suitability. Seismic wave velocity in rock varies by material: P-waves travel at approximately 5โ€“7 km/s in granite and 1.5 km/s in water, while S-waves travel at roughly 60% of P-wave speeds. Atmospheric pressure decreases with altitude according to the barometric formula: P = P0 ร— exp(โˆ’Mgh / RT), where M is molar mass of air, g is gravitational acceleration, h is altitude, R is the universal gas constant, and T is temperature in Kelvin. Standard sea-level pressure is 101,325 Pa. Tidal calculations use harmonic analysis of gravitational forcing by the Moon and Sun, with the principal lunar semidiurnal tidal constituent (M2) having a period of approximately 12.42 hours.

History

The history behind the Degree of Saturation Calculator traces back through the following developments. The systematic study of Earth's structure and processes spans millennia, but the scientific foundations were laid in the seventeenth century. In 1669, Danish naturalist Nicolas Steno published his principles of stratigraphy, establishing the laws of superposition, original horizontality, and lateral continuity โ€” foundational rules for reading rock layers that remain in use today. Scottish geologist James Hutton introduced the concept of uniformitarianism in 1788, proposing that geological processes observable in the present have operated throughout Earth's history at broadly consistent rates. This idea of deep time challenged prevailing biblical chronologies and set the stage for modern geology. Charles Lyell systematized these ideas in his landmark three-volume work Principles of Geology, published beginning in 1830, which directly influenced Charles Darwin's thinking on biological evolution during the voyage of the Beagle. The nineteenth century saw growing curiosity about continental shapes, but a coherent theory awaited Alfred Wegener, a German meteorologist who proposed continental drift in 1912, arguing that the continents had once formed a supercontinent he called Pangaea. His evidence included matching fossil records and geological formations across the Atlantic, but his mechanism was disputed for decades. The theory gained acceptance in the 1960s when seafloor spreading was confirmed through paleomagnetic studies, and plate tectonics emerged as the unifying framework of modern geoscience. The United States Geological Survey was established by Congress in 1879 to classify public lands and examine the geological structure, mineral resources, and products of the national domain. The twentieth century brought instrumental advances, including the global seismograph network deployed after World War II, initially to monitor nuclear tests, which dramatically improved earthquake detection and characterization. Satellite Earth observation began in earnest with the Landsat program launched in 1972, enabling continuous global monitoring of land use, glacier retreat, and vegetation patterns. Today, GPS networks, LIDAR scanning, and ocean-floor mapping provide centimeter-scale precision for tracking tectonic motion, sea level rise, and volcanic deformation in near real time.

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Frequently Asked Questions

The degree of saturation (S) is the ratio of the volume of water to the volume of voids in a soil mass, expressed as a percentage. A fully saturated soil has S = 100%, meaning all void spaces are filled with water. A completely dry soil has S = 0%. The formula is S = w * Gs / e, where w is gravimetric water content (as a decimal), Gs is specific gravity of solids, and e is the void ratio. This parameter is critical for determining soil behavior, particularly in fine-grained soils where saturation level affects strength and compressibility.
The degree of saturation profoundly influences soil mechanical behavior. In unsaturated soils, negative pore water pressure (matric suction) exists at the air-water interface within pores, providing apparent cohesion that increases shear strength. As saturation increases toward 100%, this suction decreases and effective stress drops, potentially leading to reduced bearing capacity and increased settlement. In slopes, rising saturation from rainfall infiltration is one of the primary triggers for landslides because it reduces shear strength while increasing the weight of the soil mass.
Physically, the degree of saturation cannot exceed 100% since voids cannot hold more water than their total volume. However, calculated values slightly above 100% can occur due to measurement errors in water content, void ratio, or specific gravity determinations. If your calculated S exceeds 100%, check your input parameters for accuracy. Common sources of error include incorrect specific gravity assumptions, volume measurement errors in the void ratio test, or water loss during sample handling.
You may use the results for reference and educational purposes. For professional reports, academic papers, or critical decisions, we recommend verifying outputs against peer-reviewed sources or consulting a qualified expert in the relevant field.
All calculations use established mathematical formulas and are performed with high-precision arithmetic. Results are accurate to the precision shown. For critical decisions in finance, medicine, or engineering, always verify results with a qualified professional.
No. All calculations run entirely in your browser using JavaScript. No data you enter is ever transmitted to any server or stored anywhere. Your inputs remain completely private.
Educational Note: This calculator is provided for educational and informational purposes. Results are based on the formulas and inputs provided. Always verify important calculations independently. NovaCalculator processes calculator inputs client-side; optional analytics follow visitor consent settings.Reviewed by: NovaCalculator Mathematics Team โ€” Verified against standard mathematical and scientific references. Last reviewed: December 2025. ยฉ 2024โ€“2026 NovaCalculator.

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Formula

S = (w * Gs) / e; n = e / (1 + e)

This Degree of Saturation Calculator computes results from your provided inputs using the calculator's underlying model.

Frequently Asked Questions

What is the degree of saturation of soil?

The degree of saturation (S) is the ratio of the volume of water to the volume of voids in a soil mass, expressed as a percentage. A fully saturated soil has S = 100%, meaning all void spaces are filled with water. A completely dry soil has S = 0%. The formula is S = w * Gs / e, where w is gravimetric water content (as a decimal), Gs is specific gravity of solids, and e is the void ratio. This parameter is critical for determining soil behavior, particularly in fine-grained soils where saturation level affects strength and compressibility.

How does degree of saturation affect soil behavior?

The degree of saturation profoundly influences soil mechanical behavior. In unsaturated soils, negative pore water pressure (matric suction) exists at the air-water interface within pores, providing apparent cohesion that increases shear strength. As saturation increases toward 100%, this suction decreases and effective stress drops, potentially leading to reduced bearing capacity and increased settlement. In slopes, rising saturation from rainfall infiltration is one of the primary triggers for landslides because it reduces shear strength while increasing the weight of the soil mass.

Can the degree of saturation exceed 100%?

Physically, the degree of saturation cannot exceed 100% since voids cannot hold more water than their total volume. However, calculated values slightly above 100% can occur due to measurement errors in water content, void ratio, or specific gravity determinations. If your calculated S exceeds 100%, check your input parameters for accuracy. Common sources of error include incorrect specific gravity assumptions, volume measurement errors in the void ratio test, or water loss during sample handling.

Is my data stored or sent to a server?

No. All calculations run entirely in your browser using JavaScript. No data you enter is ever transmitted to any server or stored anywhere. Your inputs remain completely private.

Can I use the results for professional or academic purposes?

You may use the results for reference and educational purposes. For professional reports, academic papers, or critical decisions, we recommend verifying outputs against peer-reviewed sources or consulting a qualified expert in the relevant field.

Does Degree of Saturation Calculator work offline?

Once the page is loaded, the calculation logic runs entirely in your browser. If you have already opened the page, most calculators will continue to work even if your internet connection is lost, since no server requests are needed for computation.

References

Reviewed by Daniel Agrici, Founder & Lead Developer ยท Editorial policy