Download PRISM

PRISM is free and open source software. You can download both the tool and its source code for free from below. Distribution is under the GNU General Public License (GPL), version 2.

Latest version: 4.1

The current version of PRISM is 4.1 (first released 20 Dec 2012). Major new improvements and additions since the last main release (4.0.3) are listed below. More details for individual releases are in the CHANGELOG.

  • Multi-objective model checking for MDPs
  • New explicit-state (pure Java) model checking engine
    including new methods for solving MDPs: policy iteration (-politer, -modpoliter) and Gauss-Seidel (-gs)
  • Easy generation of graphs for simulation paths in the GUI
  • CTL model checking (most operators), including counterexample/witness generation for A[G ...] or CTL E[F ...]
  • More efficient and more flexible simulation path generation (using -simpath)
  • New scripts for testing and benchmarking: prism-auto/prism-test/prism-filler

There are also some other important changes to be aware of:

  • By default, PRISM now automatically fixes deadlocks rather than treating this as an error
  • Significant changes to the underlying PRISM (Java) API
  • New (recommended) extensions for models/properties file: .prism and .props
  • The PRISM settings file ~/.prism is only read by the GUI (not command-line) by default

To access more recently developed features, try the development versions.


PRISM should run on 32/64-bit versions of all major operating systems. We distribute pre-built binary versions for various architectures. But for non-Windows platforms, it is usually easy to build from source code.

Note: Your version (32- vs 64-bit) of Java must match that of PRISM. In particular, to use the 32-bit Windows binary, make sure you are running a 32-bit version of Java.

Please select a distribution:
Current release (4.1.beta2):
Source code
Windows (32-bit) installer
Linux (64-bit) binary
Mac OS X (32-bit) binary
Mac OS X (64-bit) binary
Previous release (4.0.3):
Source code
Windows (32-bit) installer
Affiliation: (e.g. name of university/company)
Email address (optional):

Where did you hear about PRISM?  


See the installation instructions, included in the PRISM manual (which is also distributed with the tool).

If you have any problems, first check the list of common problems and questions.

If you are still stuck, post a message in the forum.

Once you have installed PRISM, you might want to look at:


39,402 downloads of PRISM to date.