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opentax.invaro.ai
OpenTax by Invaro
OpenTax by Invaro is a deterministic tax computation engine designed to run beneath AI agents. It supports complete line sets for individual Form 1040, corporate Form 1120, and fiduciary Form 1041 returns; the maker says state coverage spans 29 states and is growing. Tax rules include statutory…
Visit opentax.invaro.ai ↗ What it costs
- 7.2 No. 18on AI tax assistants
- Free planprice, as published
- Oct 8, 2026read on
What OpenTax by Invaro costs
- Evaluation Free
As opentax.invaro.ai publishes them, read Oct 8, 2026. Fees, tax and exchange rates can differ when you pay; check the provider's own page first.
Its statement
- Free plan
- Yes
- Free trial
- Not stated
- Runs on
- iPhone Android Web Windows · Mac · Linux
- Facts on record
- 14
Strengths and limits
Strengths
- Supports individual, corporate, and fiduciary return forms.
- Tax rules include citations and effective dates.
- Free evaluation has no expiry.
- Can refuse cases its rules cannot answer.
Limits
- Anonymous evaluation calls are limited to 600 requests an hour.
- State coverage spans 29 states and is growing.
- The CLI and MCP package sends an anonymous usage ping by default.
Facts we read
- Citations and proofsTax rules include statutory citations and effective dates, and computations can return a Merkle-rooted proof for offline verification. · opentax.invaro.ai, Oct 8, 2026
- Data handlingThe docs say request facts are computed in memory and not stored; usage records retain limited metadata rather than request arguments. · opentax.invaro.ai, Oct 8, 2026
- Document processingA deterministic compiler converts W-2 and 1099 boxes and birth dates into engine facts. · opentax.invaro.ai, Oct 8, 2026
- Free evaluationThe evaluation plan is free with no expiry; anonymous calls are limited to 600 requests an hour and a key raises the allowance to 6,000. · opentax.invaro.ai, Oct 8, 2026
- IntegrationsThe hosted MCP connector is presented for assistants, IDEs, agents, and automation platforms; named examples include Claude, ChatGPT, Cursor, n8n, Zapier, and Make. · opentax.invaro.ai, Oct 8, 2026
- Intended usersThe maker describes use cases for tax and accounting firms, freelancers and S-corp clients, advisory engagements, and financial planners. · opentax.invaro.ai, Oct 8, 2026
- InterfacesThe maker documents REST, MCP, and OpenAPI interfaces for the hosted service. · opentax.invaro.ai, Oct 8, 2026
- LicenseThe engine is offered under AGPL-3.0 with a commercial license also available. · opentax.invaro.ai, Oct 8, 2026
- Local useThe maker offers an installable package combining an MCP server, CLI, and HTTP host, and says the HTTP server can be self-hosted. · opentax.invaro.ai, Oct 8, 2026
- Out-of-scope casesWhen the corpus cannot answer, the engine refuses with a reason instead of estimating. · opentax.invaro.ai, Oct 8, 2026
- Privacy telemetryThe privacy page says the hosted MCP endpoint does not store or log tax facts, while the CLI and MCP package send an anonymous usage ping that can be disabled. · opentax.invaro.ai, Oct 8, 2026
- State coverageThe maker says state coverage spans 29 states and is growing. · opentax.invaro.ai, Oct 8, 2026
- Tax formsIt supports complete line sets for individual Form 1040, corporate Form 1120, and fiduciary Form 1041 returns. · opentax.invaro.ai, Oct 8, 2026
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Verdict
OpenTax emphasizes traceable computations and refusal when its rule set cannot resolve a case. Review its coverage, request limits, and license options before building it into a workflow.
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