What does 404 stand for online?

Page not found

Techies know that 404 is a Hypertext Transfer Protocol (HTTP) error code that means "page not found." You might encounter this error code when attempting to open a webpage that no longer exists or whose URL has been changed.

Those familiar with the 404 error code may use it as slang, when you ask them for information they don't have. For example, if you ask a friend for their opinion of your new GF, they might respond with "404." This means your friend doesn't want to share their opinion with you.


I tried to go to that website you told me about, but it 404'd
Really??? I wonder what happened
A 404 error page
A 404 error page

Related Slang


Updated August 29, 2023

404 definition by Slang.net

This page explains what the slang term "404" means. The definition, example, and related terms listed above have been written and compiled by the Slang.net team.

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