100 Continue

Indicates that a request from your browser (or client application) is finished and that you may continue activity on the server. Users don’t normally see this status as it’s mostly used for server communication.

Considered a general “OK” response and indicates there isn’t an actual error despite the pause in processes.

If there are no other interruptions or extra status codes then the user can proceed. If there are more errors or status codes then troubleshooting should be based on the alternate status code.

The HTTP 100 Continue informational status response code indicates that everything so far is OK and that the client should continue with the request or ignore it if it is already finished.

To have a server check the request’s headers, a client must send Expect: 100-continue as a header in its initial request and receive a 100 Continue status code in response before sending the body.