Everything you can do with OpenFisca

  • For economists

    OpenFisca allows you to use survey data to simulate the impact of a reform on a given government’s budget and on a population’s standard of living.
  • For public administrations

    OpenFisca allows you to stop building your micro-simulation software and tax & benefit calculators on your own. Instead, contribute to OpenFisca, collaborate with other administrations and reduce the bill for the taxpayer.
  • For developers

    OpenFisca allows you to easily create web applications based on your simulation results, thanks to the web API. You can build a great variety of other services by coding formulas, hosting your own instance or building your own extensions.
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How does it work?

OpenFisca is a free, reusable, modular open source project. It allows writing rules as code to improve the transparency of, and access to, the law.

  • Import input data
  • Calculate a sitation, write new laws or simulate reforms
  • Code custom extensions
  • Test the web API

An international open source community

OpenFisca has contributors worldwide! Join a community of economists, researchers, developers and law experts who get involved in turning law into code.

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