TEOS-10 software packages

Gibbs-SeaWater (GSW) Oceanographic Toolbox

The Gibbs-SeaWater (GSW) Oceanographic Toolbox contains the TEOS-10 subroutines for evaluating the thermodynamic properties of pure water (using IAPWS-09) and seawater (using IAPWS-08 for the saline part). The GSW library does not provide properties of ice or moist air (these properties can be found in the SIA library). This GSW Oceanographic Toolbox does not adhere to strict basic-SI units but rather oceanographic units are adopted.

Note that all the information buttons on the left below are independent of MATLAB, FORTRAN, C or PHP while the buttons on the right are for downloading the GSW Oceanographic Toolbox in these computer languages. The GSW Toolbox contents is particularly useful because it provides links to web pages which describe the thermodynamic theory behind each of the functions. Many of these web pages are intended to assist oceanographers gain confidence with the TEOS-10 thermodynamic approach to seawater. Again, you can access this information from these links on the left below without having MATLAB or being a MATLAB user.

If you use the GSW Oceanographic Toolbox we ask that you include a reference to McDougall and Barker (2011), whose full citation is:
McDougall, T.J. and P.M. Barker, 2011: Getting started with TEOS-10 and the Gibbs Seawater (GSW) Oceanographic Toolbox, 28pp., SCOR/IAPSO WG127, ISBN 978-0-646-55621-5.

To install the GSW Toolbox in MATLAB
you MUST add all the SUBFOLDERS to the PATH,
then you MUST run "gsw_check_functions".
See Installation instructions below for the complete installation instructions.

Installing the GSW Toolbox
Getting started with TEOS-10
Contents of the GSW Toolbox
GSW Toolbox list
Abridged GSW Toolbox list
GSW Toolbox version history
Corresponding Seawater functions in the GSW Toolbox
GSW licence
GSW Oceanographic Toolbox
GSW Oceanographic Toolbox
GSW Oceanographic Toolbox
GSW Oceanographic Toolbox

If you have any questions reguarding the software listed on this page email

The GSW toolbox has been developed in Maltab. It is currently being translated into other languages, if you wish to see the current progress or wish to participate in translating the code visit the development repository at

Seawater-Ice-Air (SIA)

The Seawater-Ice-Air (SIA) library contains the TEOS-10 subroutines for evaluating a wide range of thermodynamic properties of pure water (using IAPWS-95), seawater (using IAPWS-08 for the saline part), ice Ih (using IAPWS-06) and for moist air (using Feistel et al. (2010a), IAPWS (2010)). As a general rule, the inputs and the outputs of the algorithms in the SIA library are in basic SI units. Hence the salinity is Absolute Salinity in units of kg/kg (so that for example standard ocean Reference Salinity is input to SIA functions as 0.035 165 04 kg/kg rather than 35.16504 g/kg, in situ temperature is input as Absolute Temperature (T) in K, and pressure is input as Absolute Pressure (P) in Pa.