HTTP Status Codes Reference Online

Complete HTTP status code reference: 1xx, 2xx, 3xx, 4xx, 5xx — with descriptions, use cases, and RFC links. Free online HTTP guide.

1xx Informational

100Continue

101Switching Protocols

2xx Success

200OK

201Created

204No Content

206Partial Content

3xx Redirection

301Moved Permanently

302Found

304Not Modified

307Temporary Redirect

308Permanent Redirect

4xx Client Error

400Bad Request

401Unauthorized

403Forbidden

404Not Found

405Method Not Allowed

408Request Timeout

409Conflict

410Gone

422Unprocessable Entity

429Too Many Requests

5xx Server Error

500Internal Server Error

501Not Implemented

502Bad Gateway

503Service Unavailable

504Gateway Timeout

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What is HTTP Status Codes Reference Online?

HTTP status codes are three-digit numbers returned by servers to indicate request outcome. 1xx = informational, 2xx = success, 3xx = redirection, 4xx = client error, 5xx = server error. Essential knowledge for API development and debugging.

How to Use HTTP Status Codes Reference Online

Browse by category or search for a specific code.
Each entry includes meaning, common causes, and usage context.

Example

Status code lookup

Input

404

Output

Not Found — Resource does not exist at this URL

Frequently Asked Questions

Difference between 401 and 403?

401 Unauthorized: authentication required (no credentials). 403 Forbidden: authenticated but not permitted.

When to use 422 vs 400?

400 Bad Request: malformed syntax (invalid JSON). 422 Unprocessable Entity: valid syntax with semantic errors (missing required field).