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Step 2 of 4 · ProjectsBy tax area

All projectsBy tax areaIncome tax

166 open source projects for income tax.

Every project on the list whose tax area includes Income tax, grouped by kind. Entries without a warning come first in each group; the labels mark what to check.

166 projects133 maintained61 on the map36 jurisdictions + globalFacts checked 6 Oct 2026
Browse these by jurisdiction
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Tax engines

39 projects

Rules-as-code that compute liabilities, returns and reforms.

Calculators

48 projects

Small tools that compute one tax for one country.

Agent skills

13 projects

Packaged tax expertise an AI agent can follow, step by cited step.

MCP

10 projects

Open connectors and protocols between agents and legislation, case law and ledgers.

Plugins

2 projects

Bundles of skills, tools and agents, installable in one go.

APIs

11 projects

Validation, rates, filings and registries you can call directly.

Automations

25 projects

Reusable workflows for provisions, reconciliations and compliance runs.

Tax datasets

12 projects

Rates, treaties and statistics, open and versioned.

Legal datasets

3 projects

Statute, case law and guidance your agents can cite.

Benchmarks

3 projects

Evals that show whether a model reasons about tax, or guesses.

Labels mark what to check before you rely on an entry: inactive or archived code, demos, paid services and unclear licences. Only maintained projects for companies and tax authorities appear on the map. Search and filter the whole list.

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Next · Step 3 of 4The gapsThe activities with no open project yet, and the partly covered ones, with what to build on.