PolicyEngine simulates tax and benefit policies. Users can enter their household information in rich detail (hundreds of variables), and we estimate their taxes and benefits; they can also design a custom policy reform from hundreds of parameters and we estimate the impact on society (poverty, inequality, and the budget) and their own household. It's free, open source, and mobile friendly, and operates in the US and the UK.

We just launched a major update where we rewrote everything but the rules engine, and fully launched PolicyEngine US (previously beta).

US launch post: https://policyengine.org/us/blog/the-new-policyengine

US 15-second video: https://youtu.be/8lpXRppeq_U

US post on using PolicyEngine to model a Child Tax Credit reform: https://policyengine.org/us/blog/from-idea-to-impact-scoring...