PHREEQC Version 3

Release Date:

Overview of PHREEQC Version 3

Chemical waves of the Belousov reaction that are calculated with PHREEQC.

Chemical waves of the Belousov reaction that are calculated with PHREEQC.

PHREEQC Version 3 is a computer program written in the C++ programming language that is designed to perform a wide variety of aqueous geochemical calculations. PHREEQC implements several types of aqueous models including two ion-association aqueous models.


  •  Version 3.0--Documentation of all features, including high pressure calculations, charting (Windows), Pitzer and SIT activity-coefficient models, CD-MUSIC surface complexation, and isotope capabilities. Updated PhreeqcI. Additional methods for IPhreeqc modules.


  •  PhreeqcRM--Reaction module for reactive-transport simulators. Based on IPhreeqc, allows access to all PHREEQC reaction capabilities. Contains methods for initial and boundary conditions, running reactions on all model cells, transfer of data to and from the module, and parallelization by MPI or OpenMP.


Download Current Version of PHREEQC


Graphical User Interfaces

Batch Versions of PHREEQC

PhreeqcRM Reaction Module for Transport Models

IPhreeqc Modules


Documentation for PHREEQC


Additional Information

General Information

Release Notes and Readme Files

Other Resources


Software License and Purchase Information

This software is a product of the U.S. Geological Survey, which is part of the U.S. Government.


This software is freely distributed. There is no fee to download and (or) use this software.


Users do not need a license or permission from the USGS to use this software. Users can download and install as many copies of the software as they need.

Public Domain

As a work of the United States Government, this USGS product is in the public domain within the United States. You can copy, modify, distribute, and perform the work, even for commercial purposes, all without asking permission. Additionally, USGS waives copyright and related rights in the work worldwide through CC0 1.0 Universal Public Domain Dedication (