HTTP status codes reference

All 38 HTTP status codes, each with the causes we actually see in production, the fix, and the SEO consequence of leaving it in place.

All status codes

• 100 Continue
• 101 Switching Protocols
• 102 Processing
• 103 Early Hints
• 200 OK
• 201 Created
• 204 No Content
• 206 Partial Content
• 301 Moved Permanently
• 302 Found (Temporary Redirect)
• 303 See Other
• 304 Not Modified
• 307 Temporary Redirect
• 308 Permanent Redirect
• 400 Bad Request
• 401 Unauthorized
• 403 Forbidden
• 404 Not Found
• 405 Method Not Allowed
• 408 Request Timeout
• 410 Gone
• 413 Payload Too Large
• 414 URI Too Long
• 418 I'm a Teapot
• 422 Unprocessable Entity
• 429 Too Many Requests
• 451 Unavailable For Legal Reasons
• 500 Internal Server Error
• 502 Bad Gateway
• 503 Service Unavailable
• 504 Gateway Timeout
• 507 Insufficient Storage
• 508 Loop Detected
• 511 Network Authentication Required
• 521 Web Server Is Down
• 522 Connection Timed Out
• 523 Origin Is Unreachable
• 524 A Timeout Occurred