200 – OK: The standard HTTP response for successful HTTP requests. In another way, the web server will return 200 when requested content is served successfully.
202 – Accepted: The server has accepted your request and yet to process them.
206 – Partial Content: Only partial content is delivered due to the range header sent by a client like wget.
301 – Moved permanently: Your requested page has been moved permanently to a new location. This instructs search engine bot to crawl new location.
302 – Moved temporarily: Your requested is served from a different location but that is temporary arrangement. This instructs search engine bot to crawl the original location.
305 – Use proxy: The requested resource is only available through a proxy. That means you must use a relevant proxy to get the requested page successfully.
304 – Not modified: Usually when cached page is served when a resource has not been modified.
400 – Bad request: The server is confused what you have requested. Probably bad syntax or trying to include characters in URI which server doesn’t understand.
401 – Not authorised: The requested page is protected and requires authentication. You must login in order to get the requested page successfully.
403 – Forbidden: You have to try to access which you don’t have permission. This, not necessary resource is protected by the password; it could also be when files/folder permission doesn’t allow viewing the requested page.
404 – Not found: Probably the most famous one – your requested page is not found on the server. You are trying to access something, which doesn’t exist.
405 – Method not allowed: You are requesting a page with the wrong method. For example, you are doing GET on POST data. Or you are trying the method, which is disabled for example – TRACE, PUT, DELETE.
408 – Request timeout: The server timed out waiting for the request
411 – Length required: Your request doesn’t meet the length of its content, which is required by the requested resource.
500 – Internal server error: A very generic error when server encountered an error due to various reasons. Logs must be examined to see why the server has responded internal error.
502 – Bad gateway: The server was acting as a gateway or proxy and received an invalid response from the upstream server like Tomcat, WebSphere.
503 – Service unavailable: The server can’t serve your request. This could be due to either server is too busy in other stuff or almost dead.
I hope now you have an idea about HTTP status return code. If you find this useful, help in sharing with your friends.