Modern online modeling software

Think Forward, Think Clearly

Whether your bank account, the customers of a restaurant, or the trees in the rainforest, the world is driven by the changes of things over time. Sysdea makes it simple to start modeling these systems, giving easy predictive power, while remaining easy to understand and show to others.

It's free to try, with nothing to install, and no need to register to try the tutorial.

Once you've registered you'll have a 30 day free trial.

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See your current situation, and explore alternative choices into the future.

Simple Principles, Powerful Results

Sysdea modeling is based upon Stocks (something that accumulates, such as money in a bank account, trees in a forest) and Flows (the forces that cause such Stocks to accumulate and deplete). With just these two concepts and supportive Variables to allow intermediate calculations, you get great expressive power.

Each time you make a change the model instantly updates, having such quick feedback allows you to rapidly build models with confidence. There's no worries about cell references and copying formulae as in a spreadsheet, and charts attached to everything allow easy at-a-glance inspection of behaviour.


Standard 15$/month
30 day free trial
60 day money-back guarantee
Teachers Free
Discounted short-term student accounts
Class management features coming soon

Quick and Simple

Building models is enough work already, without the software slowing you down. Sysdea's simple shortcuts, auto-completion and fast error feedback mean anyone can be building working models in minutes - ideal for teaching, and saving time for professional users.

Share Instantly

Because all of your models are hosted on Sysdea servers, showing someone your model is as easy as creating a share link and sending it to them. With nothing to install, all they need is a recent browser to be able to instantly see your model in action.

Match the real world

Getting models to match real-world behaviours is critical. Sysdea supports a user data series which is always visible, to compare your simulation against. This lets you put in past numbers, get your model to follow, and build confidence in it's future predictions.

Total clarity

We know people find it hard to understand how complex systems drive behaviour over time, so Sysdea shows time-charts on every object, and makes stock-flow relationships explicit ... no more puzzling over the reasons for your model's results.