How to convert specific conductivity to salinity

Updated March 23, 2017

The word "specific," when used in physics and chemistry, has a (specific) meaning. It refers to a quantity divided by an extensive (dimensional) measure to make it a measure of a substance's properties instead of peculiar to a particular object. For example, specific conductivity (or just conductivity, which by definition already is a specific measure) measures a substance's ability to conduct electricity. Scientists measure conductivity in seawater to determine salinity. While the conversion from the former to the latter uses a long equation of several terms, you can use an online calculator to make the conversion with just three variables.

Convert your conductivity measurement's unit from siemens per meter (S/m) to milli-siemens per centimetre (mS/cm). In other words, multiply by 10.

Raise the conductivity (in mS/cm) to the power 1.0878.

Multiply the result by 0.4665. This gives you salinity in grams (of salt) per litre (of solution).


An accurate conversion for salinity ranges 5 to 100 milli-siemens per centimetre, or 0.5 to 10 S/m. This is useful for aquariums, freshwater and saltwater. The above parameters apply to 25 degrees Celsius.

Cite this Article A tool to create a citation to reference this article Cite this Article

About the Author

Paul Dohrman's academic background is in physics and economics. He has professional experience as an educator, mortgage consultant, and casualty actuary. His interests include development economics, technology-based charities, and angel investing.