U.S. Tax Law. Searchable. Browsable. Free.

Federal and state statutes, regulations, and guidance. Navigable, updated, and built for how tax professionals work.

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Tax Library is the most navigable collection of U.S. tax law on the web. It's also the source powering every cited answer in Marble Intelligence.

Find What You Need, Fast

Browse the tax code or search for what you need. Intelligent matching and autocomplete get you to the right provision without memorizing section numbers or learning rigid query syntax.

Read Provisions in Context

Navigate from title to chapter to section with structured table of contents. Context matters in tax law, and Tax Library keeps surrounding provisions and code structure visible.

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Tax Library is free and publicly accessible. Send a direct link to any page, whether it's for a colleague, a client, or your own reference. No login required to read it.

Tax Jurisdiction Coverage

Research Coverage ensures that Feather uses all available, up-to-date, authoritative government resources for Federal and State and US Territory-Level tax laws. Authoritative Citations are verified references to official sources.

Jurisdiction

Research Covered

Authoritative Citations

Delaware

Pennsylvania

Illinois

Nevada

Washington

Arizona

New Jersey

Minnesota

Minnesota

Minnesota

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