Fair use is a legal doctrine that allows limited use of copyrighted material without permission under 17 U.S.C. §107. Whether something qualifies as fair use is determined by weighing four factors — there are no bright-line rules, and courts decide on a case-by-case basis. This interactive checklist helps you analyze each factor systematically. This tool provides general information only, not legal advice. Consult a licensed attorney for legal guidance specific to your situation.

1

Purpose and Character of Use

Is the use commercial or non-profit/educational? Is it transformative?

Key case: Campbell v. Acuff-Rose (1994) — 2 Live Crew's parody of "Oh, Pretty Woman" was fair use because it was transformative commentary. Transformativeness is the most important subfactor in modern fair use analysis.
2

Nature of the Copyrighted Work

Factual works receive less protection than creative works.

Key case: Harper & Row v. Nation Enterprises (1985) — The Nation magazine's use of unpublished Ford memoirs was not fair use. Unpublished works get strong protection because authors have the right to control first publication.
3

Amount and Substantiality Used

How much was taken, and was the "heart" of the work used?

Key case: Harper & Row (1985) — Even though only 300 words of a 200,000-word book were used, they were the "heart" of the work (Ford's reflections on pardoning Nixon). Amount is qualitative, not just quantitative.
4

Effect on the Potential Market

Does your use harm the market for the original or its licensing?

Key case: Sony Corp. v. Universal City Studios (1984) — Home VCR recording for time-shifting was fair use partly because there was no evidence of harm to the market for the original TV broadcasts.