Seawater Density Calculator

This calculator solves the Equation of State of Seawater.

Enter temperature and salinity to find density σt.
Enter temperature, salinity and pressure to find in-situ density σStp.


Enter your values:

temperature (°C):    salinity:    pressure (10 kPa):

   σt =    σStp =

Note: 10 kPa = 1 dbar is close to the pressure increase that corresponds to a depth increase of 1 m.
Entering a pressure value equal to the depth in metres will give an approximate result.

Add 1000 to the result to obtain density in kg m-3.

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 Sciences 44, 53 pp.

© 2000 M. Tomczak. Last updated 2 April 2000

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