TOPAS wraps and extends the Geant4 Simulation Toolkit. The following table lists the TOPAS versions that introduced a new version of the Geant4 library.

TOPAS version Geant4 version
3.1.0 10.3.p01
3.0.0 10.2.p01
2.0.0 10.1.p02
1.0.0 9.6.4

A detailed list of changes introduced by each TOPAS version can be found below:

Prior to the release of version 1.0, TOPAS had a long public beta phase.