AI engineering glossary · Web APIs HTTP
What is 404 Not Found?
404 Not Found: The status code meaning the server has no resource at the requested URL. It can reflect a typo, a deleted item or a server deliberately hiding a resource the caller may not see.
404 Not Found: an example
GET /users/99999 returns 404 when no such user exists.
Related terms
More Web APIs HTTP terms
- 409 Conflict
- 422 Unprocessable Content
- 429 Too Many Requests
- 500 Internal Server Error
- 502 Bad Gateway
- 503 Service Unavailable
- 504 Gateway Timeout
- Accept header
Where you learn it
404 Not Found is part of the AI Engineering Program, which teaches it with notes, a hands-on lab and an exam. The first lesson is free.