FastOS Tools
FastOS Tools

HTTP Status Code Explainer

Explain HTTP status codes. Understand what each status code means and when to use it.

Search Status Code

Common Status Codes

200OK
The request succeeded.
201Created
The request succeeded and a new resource was created.
204No Content
The server successfully processed the request but is not returning any content.
301Moved Permanently
The URL of the requested resource has been changed permanently.
302Found
The URL of the requested resource has been changed temporarily.
304Not Modified
The resource has not been modified since the last request.
400Bad Request
The server cannot process the request due to a client error.
401Unauthorized
Authentication is required and has failed or has not been provided.
403Forbidden
The server understood the request but refuses to authorize it.
404Not Found
The server cannot find the requested resource.
500Internal Server Error
The server encountered an unexpected condition.
502Bad Gateway
The server, while acting as a gateway, received an invalid response.
503Service Unavailable
The server is temporarily unable to handle the request.

Introduction

The HTTP Status Code Explainer tool describes what each HTTP status code means and when it is typically used. It is helpful for debugging APIs and understanding server responses.

When to use this tool

Use this tool whenever you encounter an unfamiliar status code in logs, browser devtools, or API responses.

How to use

1

Enter a status code

Type a numeric HTTP status code like 200, 301, 404, or 500.

2

Read the explanation

See a short description of the code, its category, and common usage scenarios.

Examples

Understanding 4xx vs 5xx errors

Look up codes like 400, 403, 404, or 500 to see whether the problem is likely on the client side or server side.

FAQ

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