418 I'm a teapot

4xx Client error

A joke code: the teapot refuses to brew coffee. It began as an April Fools RFC.

On the wireHTTP/1.1 418 I'm a teapot
Code418
Is it an errorYes — this is an error
Category4xx Client error

The problem is on the request side; sending the same thing again will fail again.

How to read this

  • The first digit of a status code carries the meaning: 4 means the request, 5 means the server.
  • 404 means "not there"; 403 means "there, but not for you". Swapping them makes debugging slower.
  • Header names are case-insensitive — Content-Type and content-type are the same header.
  • Caching and CORS problems usually come down to one header line, visible in the browser’s network tab.

Frequently asked questions

Q. What does HTTP 418 I'm a teapot mean?

A joke code: the teapot refuses to brew coffee. It began as an April Fools RFC.

Q. What does 418 I'm a teapot look like on the wire?

It travels as HTTP/1.1 418 I'm a teapot

Q. Is 418 I'm a teapot an error?

Yes. A code starting with 4 blames the request; one starting with 5 blames the server.

Q. What group does 418 I'm a teapot belong to?

The 4xx client error group; the rest of that group is listed further down.

Same group

Reference docs