Thermo-Calc Software is a well-established company with an interesting history.

Watch our 20th anniversary video to learn about the history, complete with photos dating back to the 1970s, or scroll on to read the story. 

Thermo-Calc Software was founded in 1997, but it all really started much before that. Actually, already in the mid 70’s. The place was the department for physical metallurgy at the Royal Institute of Technology in Stockholm, Sweden (KTH), where Mats Hillert was a professor. Three of his graduate students at this time were:

  • Bo Sundman
  • Bo Jansson
  • John Ågren

They all had different projects, but with the common factor that they all needed access to thermodynamic data. The three students decided to join forces and write a more general program for thermodynamic calculations which did not need to be modified for each new system that was to be introduced.

Read more about the history of computational thermodynamics at KTH in this fascinating presentation by John Ågren: Education in Computational Thermodynamics, ICME and Materials Design – the KTH experience » 

The result was Thermo-Calc and the first version was ready in 1981. Fortunately, all three students decided to stay in the department after graduation and could thereby continue to work on the software. Only a few years later, the reputation of this software had spread and other researchers in academia, as well as in industry, expressed large interest in using Thermo-Calc.

One of the students, John Ågren, had a project on a topic of simulation of diffusion controlled phase transformations, and this work eventually resulted in the DICTRA software, now known as the Diffusion module (DICTRA).

Later, several other individuals also made contributions to the software, e.g. Lars Höglund, Jan-Olof Andersson, Björn Jönsson and Anders Engström, and in order to make sure that the intellectual property of the software was under the control of a single entity, the seven researchers created a foundation to which they donated their respective individual rights. This was done in 1993 and the name of the foundation was “Stiftelsen för Tillämpad Termodynamik” (STT). The purpose of this foundation was and still is to support research in the field of computational thermodynamics. This is achieved annually by distributing scholarships to young researchers who are active in this field.

A few years later, in 1997, the company Thermo-Calc Software AB was established. STT became (and still is) the majority owner. A company was created because commercial activity was not consistent with the institute's academic mission, but was necessary in order to support a growing number of users. From the start, the company has experienced continuous growth and has been steadily maturing.


  • 1969: Formation of CALPHAD
  • 1971: Sublattice model for 2 components. (Hillert & Staffansson KTH*)
  • 1977: Development of Thermo-Calc starts
  • 1977: KTH* member of SGTE
  • 1981: First version of Thermo-Calc
  • 1981: Sublattice model for multi-component systems
  • 1982: First commercial training course for external users
  • 1984: First sale of Thermo-Calc Classic
  • 1984: First sale of the TCFE database
  • 1986: First version of Thermo-Calc for VAX/VMS
  • 1988: SGTE solution database (SSOL)
  • 1990: First UNIX version of Thermo-Calc
  • 1992: Thermo-Calc 32-bit DOS/Windows version
  • 1994: First sale of DICTRA
  • 1997: The company Thermo-Calc Software is formed
  • 2000: First version with a Graphical User Interface is launched
  • 2004: The subsidiary Thermo-Calc Software Inc. is formed
  • 2011: First sale of TC-PRISMA
  • 2013: Release of the new generation of Thermo-Calc
  • 2013: First Mac OS X version of Thermo-Calc
  • 2014: DICTRA is integrated into Thermo-Calc
  • 2014: First Mac OS X version of DICTRA
  • 2015: Release of the Property Model Calculator
  • 2016: TC-PRISMA is integrated into Thermo-Calc
  • 2016: First Mac OS X version of TC-PRISMA
  • 2016: DICTRA is renamed Diffusion module (DICTRA)
  • 2016: TC-PRISMA is renamed Precipitation module (TC-PRISMA)
  • 2017: The Diffusion module (DICTRA) is released in the graphical mode
  • 2017: Introduction of User Developed Models for the Property Model Calculator
  • 2018: Release of TC-Python
  • 2018: First material-specific Property Model Library, the Steel Model Library 
  • 2019: Release of the Process Metallurgy Module for steel and slag applications 

*KTH=The Royal Institute of Technology, Stockholm, Sweden