SelfTax
SelfTax is a free tax-preparation project that reads tax documents, calculates a federal return, and fills supported free IRS filing sites.
What SelfTax is
SelfTax is a free tax-preparation project that reads tax documents, calculates a federal return, and fills supported free IRS filing sites. Its calculations use deterministic code, and each line can be audited. Structured IRS forms are processed locally. For unstructured documents, identifying details are replaced with tokens on the device before text is sent for AI interpretation; the README says names, addresses, and Social Security numbers are stored in browser local storage and never transmitted. Verified support for tax year 2025 includes W-2 wages, rental income with passive activity loss, capital loss carryover, itemized deductions, child tax credit, dependent care credit, and QBI deduction. Schedule C, K-1, education credits, EITC, AMT, and self-employment tax are listed as built but not fully tested. Users build and load it as a Chrome extension. An optional local HTTP server uses the Claude Code CLI for redacted document parsing, with the user's Anthropic API key managed by that CLI. SelfTax can also run as an MCP server for Claude Code, with tools for tax-folder scanning, profile setup, document viewing, calculation, and form generation. It is licensed under AGPL-3.0, which requires products or services built using its code to open-source their version under the same license.
Good
- Tax calculations use deterministic, auditable code.
- Structured IRS forms are processed locally.
- Supports several verified tax-year 2025 situations.
- Available as a Chrome extension and MCP server.
Watch out
- Several listed features are built but not fully tested.
- The optional local server uses the Claude Code CLI.
- AGPL-3.0 requires derivative products or services to open-source their version.
Who it suits
SelfTax is aimed at people who want to avoid paying for tax preparation or spending hours filing. Its stated support is for personal federal returns through supported free IRS filing sites.
Verdict
SelfTax offers a free route to prepare supported federal returns, with locally processed structured forms and auditable calculations. Its verified coverage is specific, so users should distinguish that list from features marked built but not fully tested.
Plans and prices
From SelfTax's own pricing page, checked 8 Oct 2026.
| Plan | Price | What it gives you |
|---|---|---|
| Free | Free | Free AI-powered tax preparation · federal return · supported free IRS filing sites |
The facts
Each one read from SelfTax's own pages, with the date it was checked.
Where it runs
- Browser extension
- The README instructs users to build and load SelfTax as a Chrome extension.checked 8 Oct 2026
What it does
- Document parsing
- Structured IRS forms are processed locally; AI is used only to parse unstructured documents when needed.checked 8 Oct 2026
- Intended user
- The maker describes the project as built for people who want to avoid paying for tax preparation or spending hours filing their taxes.checked 8 Oct 2026
- Local server
- An optional local HTTP server uses the Claude Code CLI to parse redacted documents, and the user’s Anthropic API key is managed by that CLI.checked 8 Oct 2026
- MCP integration
- SelfTax can run as an MCP server for Claude Code and exposes tools to scan tax folders, set a profile, view documents, calculate taxes, and generate forms.checked 8 Oct 2026
- Open-source license
- SelfTax is licensed under AGPL-3.0, which the README says requires products or services built using the code to open-source their version under the same license.checked 8 Oct 2026
- Privacy
- The README says SSNs, names, and addresses are stored in browser local storage and never transmitted.checked 8 Oct 2026
- Purpose
- SelfTax reads tax documents, calculates a federal return, and auto-fills supported free IRS filing sites.checked 8 Oct 2026
- Redaction
- Before unstructured document text is sent for AI interpretation, the README says identifying details are replaced with tokens locally.checked 8 Oct 2026
- Supported filing
- Tested and verified support includes W-2 wages, rental income with passive activity loss, capital loss carryover, itemized deductions, child tax credit, dependent care credit, and QBI deduction for tax year 2025.checked 8 Oct 2026
- Tax calculations
- Tax calculations use deterministic code, and the README says each line can be audited.checked 8 Oct 2026
- Unverified coverage
- The README lists several features as built but not fully tested, including Schedule C, K-1, education credits, EITC, AMT, and self-employment tax.checked 8 Oct 2026
