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HTTP Status Codes Reference

Complete guide to understanding every HTTP status code. Learn what each code means in plain English, common causes, how to fix errors, and the impact on SEO and user experience.

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Most Common HTTP Status Codes

Quick reference for the status codes you'll encounter most often

HTTP Status Code Lookup

Enter a status code to see detailed information

Understanding

HTTP Status Codes

HTTP status codes are three-digit numbers returned by servers to indicate the result of a request. They're essential for understanding what's happening between your browser and a website's server. Whether you're debugging, optimizing for SEO, or monitoring uptime, understanding status codes helps you quickly identify and resolve problems.

Categories

Status Code Categories

1xx Informational

Indicate that the request was received and the process is continuing. Rarely seen by end users.

2xx Success

The request was successfully received, understood, and accepted. Everything worked as expected.

3xx Redirection

Further action needs to be taken to complete the request. The resource has moved or additional steps are required.

4xx Client Error

The request contains bad syntax or cannot be fulfilled due to client-side issues.

5xx Server Error

The server failed to fulfill an apparently valid request. These need immediate attention.

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