HTTP response codes

Response codes

The first line of the HTTP response is the state drain. It consists of two parts: a three-digit number (response code) and a text message (response description).

RESPONSE-CODE TEXT-DESCRIPTION

The client learns the status of its request from the response code and decides what to do next. Examples of different responses from the server:

Response codes are divided into 5 categories. The first digit of the response code determines which category it belongs to.

All answers starting with the number 1 are classified as informational. We will not talk about them in detail ...

Response code 200

After all, there are others that are much more interesting to us. All responses that look like 2xx are successful. The response most loved by programmers is 200 OK , which means that everything is fine, the request was successfully completed.

You may also find this list of other “good” answers helpful:

Response codes 301, 302

Responses that look like 3xx are in the redirect class . They indicate that the resource has been moved to another location.

The most popular of them:

• 301 - moved permanently
• 302 - moved temporarily

In the colloquial speech of programmers, you will often hear “302 redirect” or “301 redirect” - this is just about it.

Full list of 300 replies:

Response code 404

All answers that start with the number 4 indicate a client-side error , and there are a lot of them. The most popular you know for sure: this is the answer “404 - not found”.

Other common answers are given in the table:

Response code 501

And finally, the last category is server-side errors. All such errors start with the number 5. The most common error for a developer is 501 (functionality not implemented). Sometimes it happens.

In general, get acquainted with these error codes, they are now your friends for the rest of your life. Well, as usual, here is a table with the most useful error codes on the server side: