What is an HTTP status code?

An HTTP status code is a 3-digit number returned by a server in response to a client request. It tells the client whether the request succeeded, failed, or needs further action.

What is the difference between 401 and 403?

401 Unauthorized means the client is not authenticated — no valid credentials were provided. 403 Forbidden means the client is authenticated but does not have permission to access the resource.

What is the difference between 301 and 302?

301 Moved Permanently tells search engines and browsers the URL has changed forever — they should update bookmarks and transfer SEO value. 302 Found is a temporary redirect — the original URL remains canonical.

What causes a 500 error?

500 Internal Server Error means something went wrong on the server that it cannot recover from. It is a generic catch-all for unhandled exceptions. Check server logs for the specific cause.

429 Too Many Requests means the client has sent too many requests in a short time window (rate limiting). The server may include a Retry-After header indicating when to try again.

What is the 418 status code?

418 I'm a Teapot is from RFC 2324 (an April Fools RFC) where a teapot refuses to brew coffee. Despite being a joke, it is a registered IANA status code and used playfully by many real servers.

HTTP Status Codes Reference - Complete List Free

Complete reference for all HTTP status codes with descriptions: 1xx informational, 2xx success, 3xx redirection, 4xx client errors, 5xx server errors.

2xx Success

3xx Redirection

4xx Client Errors

5xx Server Errors

61 HTTP status codes · RFC 9110 + extensions

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What is HTTP Status Codes Reference — Complete List with Descriptions?

HTTP status codes are 3-digit numbers returned by web servers to indicate the result of a client request. They are grouped into five classes: 1xx (informational), 2xx (success), 3xx (redirection), 4xx (client errors), and 5xx (server errors). Understanding status codes is essential for web development, API design, SEO, and debugging.

How to Use HTTP Status Codes Reference — Complete List with Descriptions

1Search for a specific code by number (e.g. 404) or name (e.g. Not Found).
2Filter by category using the category buttons (2xx Success, 4xx Client Errors, etc.).
3Click any code to expand its full description.

Key Features

All 60+ standard HTTP status codes
Full description for each code
Search by code number, name, or description
Filter by category (1xx through 5xx)
RFC 9110 compliant definitions

Benefits

Quickly understand API error responses during development
Choose the correct status code for REST API responses
Debug redirect chains and SEO issues (301 vs 302 vs 307)
Understand security-related codes (401 vs 403)

Why Use Irreva for HTTP Status Codes Reference — Complete List with Descriptions?

Quickly understand API error responses during development

Choose the correct status code for REST API responses

Debug redirect chains and SEO issues (301 vs 302 vs 307)

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