What Is BYOK, Bring Your Own Key?

BYOK means a tool lets users provide their own API key instead of the tool owner paying for all AI usage.

BYOK stands for bring your own key. In an AI app, it usually means the user pastes their own OpenAI, OpenRouter, Anthropic, or other API key into the app so requests are billed to the user account.

In practice

BYOK is useful for prototypes, personal tools, classrooms, internal utilities, and niche apps where users want control over model choice and spending.

What to watch

BYOK requires trust. The app should explain where the key is stored, how it is used, and how users can remove or rotate it.