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Enter your values: red boxes are mandatory
Rt, conductivity ratio: *

T (ºC), temperature: *

S =


This calculator derives salinity from a value of the conductivity ratio, Rt, (as determined, for example, by a salinometer) and temperature T. The conductivity ratio for this calculator is defined as

\[ R_t(S, T) = \frac{C(S, T, 0)}{C(35, T, 0)} \]

where S is salinity, T is temperature and C is conductivity. This is the quantity used in the determination of salinity, for example, in bench salinometers. To determine salinity from direct measurements of in situ conductivity (as, for example, in CTDs) use the salinity from conductivity, temperature and pressure calculator.


Temperature uses IPTS-68, salinity uses PSS-78; see reference.

Calculation based on Fofonoff, P. and R. C. Millard Jr (1983) Algorithms for computation of fundamental properties of seawater. Unesco Technical Papers in Marine Science 44, 53 pp.