We are pleased to announce the release of StochSS: Stochastic Simulation Service, Version 1.5. StochSS is an integrated development environment for modeling and simulation of discrete stochastic biochemical systems. An easy to use GUI enables researchers to quickly develop and simulate biological models on a desktop or laptop, which can then be expanded or combined to incorporate increasing levels of complexity. As the demand for computational power increases, StochSS is able to seamlessly scale up by deploying cloud computing resources. The software currently supports simulation of ODE and well-mixed discrete stochastic models, parameter estimation of discrete stochastic models, and simulation of spatial stochastic models.

New capabilities of Version 1.5 include:
  • A new model editor: Edit models faster and easier
  • Cost analysis functionality: Measure the cost of running jobs in the cloud
  • Cloud data reproduction: Delete cloud data and reproduce it only when it is needed
  • Cloud instance type selection: Configure what instance types are used for cloud computation
For more details and instructions on how to obtain the code, visit us at

Linda Petzold and Chandra Krintz
University of California Santa Barbara

Per Lotstedt and Andreas Hellander
Uppsala Universiteit


StochKit: a Stochastic Simulation Toolbox for Biology

Other Downloads


  • DASSL and DASPK2.0 are available in the public domain.
  • DASPK3.1 is subject to copyright restrictions, but is available for research purposes. It may still be subject to revision. This latest version of DASPK3.1 includes the root-finding DAE solver DASKR (root-finding modifications to DASPK3 done by Alan Hindmarsh, LLNL). DASPKAdjoint, which uses the adjoint method for computing the sensitivity coefficients, is also included.