Fair use is not a shortcut

Why fair use is a case-by-case legal defence, not a label you can attach to a video.

Many creators hope that writing "fair use" in a description will protect a video. It does not. This article is general information and not legal advice; fair use and similar exceptions differ between countries, and some places have no such doctrine at all.

What it is

Fair use, where it exists, is a legal defence. It is not a tag, a setting or a permission. It is judged by a court or decision-maker, case by case, after a use has been challenged. Nobody can tell you in advance, with certainty, that your video is covered.

What is usually weighed

Assessments generally look at questions such as:

The purpose of the use. Is it commentary, criticism, teaching or news, or is it just entertainment taken from someone else?
The nature of the original work.
How much was used, and how central it was.
The effect on the owner's ability to benefit from the original.

No single question settles it, and there is no safe length or percentage. Short does not mean allowed.

What it is not

Not permission. It does not replace a licence.
Not a claim-remover. Mentioning it does not release a claim or reverse a strike. See Claim or strike?.
Not credit. Naming the owner has nothing to do with the question.
Not platform policy. The platform's rules are separate from copyright law, and the platform can still act on a claim.

Some common beliefs, set against reality:

Fair use myths versus reality

	Common belief	Reality
A label	A tag in the description protects me	A defence judged case by case
Credit	Naming the owner helps	Credit is not the question
Short clips	Short means allowed	No safe length exists
Claims	Mentioning it cancels a claim	It does not release a claim

A sensible approach

Prefer permission: make your own material or use something properly licensed. See the Licensing evidence checklist.
If you rely on an exception, be able to explain why: what you add, why you needed the material and how little you used.
Expect that you may be asked to justify it, and that the other side may disagree.
For anything important, talk to a lawyer first.
Never use the phrase to dispute a claim without a reasoned basis.

Related lessons: Copyright basics and Reused content.

Always check the source

Platform processes and consequences are set by YouTube and can change. Read the current official page before you act.