Rotate the screen

Free simulation software OpenSIMPLY

OpenSIMPLY is a discrete event simulation software that runs on Windows and Linux on 32-bit and 64-bit platforms as a graphical or terminal application.

Write your model once, simulate anywhere.

The OpenSIMPLY is an completely free software with very high simulation performance.

Don't wait for years, get simulation results now.

The OpenSIMPLY 3.0.1 has been released. Simulation results can be obtained almost twice as fast.


The project is open source software, and currently the following programming languages ​​and IDEs are suporrted:

Simulation with OpenSIMPLY is suitable for people of any experience. Creating a simulation model is very easy - just a few lines and the model is ready to run. Look at the code of simulation examples.

OpenSIMPLY as modeling software offers two styles of computer simulation: block simulation and Simula-like simulation. Both of them provides discrete event simulation approach but at different levels.

When block simulation, a certain block represents ready to use model component, for example a queue or a server or a router. The blocks should be connected in the required order, and the necessary parameters may be specified. Any simulation block can be extended in terms of parameters and functionality.

The second style is an advanced one and very similar to the Simula programming language. The user may create more faster simulation models. Even the models in Simula with some adaptation can run with OpenSIMPLY.

Both styles can be used together. The simulation blocks can be used for the general description of system behavior, and the critical section can be written with advanced simulation technique.

Learn more about the simulation styles.

OpenSIMPLY implements global, selective and deferred statistics gathering modes. The last one allows the user to take into account the steady state of the model to prevent significant decrease in the accuracy of the results.

Project provides full flexibility to describe the behavior of the model using dynamic model. Blocks may be relocated during the simulation, and a model can change its configuration on runtime.

OpenSIMPLY contains documentation with runnable examples, insight help (pop-up hints) for Delphi and Lazarus IDEs and a tutorial with executable examples for step by step learning. Watch learning videos.

Areas of use

Scientific research When using a model for a system under study, any characteristic requires at least several simulation points. In practice, for a good (smoothed) characteristic, quite a few such points are needed.
For an acceptable error (for a given confidence interval), the number of entities (objects) in the simulation model should be large enough to run, especially for complex systems.
Therefore, the simulation software should work very fast (and, of course, correctly) so that you do not have to wait a few days to get the results.
OpenSIMPLY is very fast and capable of automatically multi-pass simulating of the same model with different input data. Flexible formatted output of OpenSIMPLY is suitable for both approximation tables and visualization. learn more

Traffic simulation The project was originally developed for traffic analysis with a clear and simple modeling ideology. Built-in traffic theory routines help validate simulation results for some degenerate cases, which allows even complex models to be verified. learn more

Network simulation With OpenSIMPLY a fairly complex and large networks can be simulated as well. Simulation blocks of network routers, of packet filters, of broadcasting, and more make it easy to create models of network architectures. The entire network route of any packet can be saved and analyzed. learn more

Education Open SIMPLY is great for educational purposes. Due to the strongly typed programming language, beginners make fewer mistakes, but may pay more attention to the study of the simulation approach. learn more

Licenses and special requirements

OpenSIMPLY is free computer simulation software. Learn more about the using.

For special agreement or for extra features write a message.

You can help

Share the project in social.