| Informational 1xx |
| 100 | Continue |
| 101 | Switching Protocols |
| 102 | Processing (WebDAV RFC 2518) |
| 103 | Early Hints (experimental RFC 8297) |
| Successful 2xx |
| 200 | OK |
| 201 | Created |
| 202 | Accepted |
| 203 | Non-Authoritative Information |
| 204 | No Content |
| 205 | Reset Content |
| 206 | Partial Content |
| 207 | Multi-Status (WebDAV RFC 2518) |
| 208 | Already Reported (WebDAV RFC 2518) |
| 210 | Content Different (WebDAV RFC 2518) |
| 226 | IM Used (RFC 3229) |
| Redirection 3xx |
| 300 | Multiple Choices |
| 301 | Moved Permanently |
| 302 | Found |
| 303 | See Other |
| 304 | Not Modified |
| 305 | Use Proxy |
| 306 | (Unused) |
| 307 | Temporary Redirect |
| 308 | Permanent Redirect |
| 310 | Too many Redirects |
| Client Error 4xx |
| 400 | Bad Request |
| 401 | Unauthorized |
| 402 | Payment Required |
| 403 | Forbidden |
| 404 | Not Found |
| 405 | Method Not Allowed |
| 406 | Not Acceptable |
| 407 | Proxy Authentication Required |
| 408 | Request Timeout |
| 409 | Conflict |
| 410 | Gone |
| 411 | Length Required |
| 412 | Precondition Failed |
| 413 | Request Entity Too Large |
| 414 | Request-URI Too Long |
| 415 | Unsupported Media Type |
| 416 | Requested Range Not Satisfiable |
| 417 | Expectation Failed |
| 418 | I’m a teapot (RFC 2324) |
| 421 | Bad mapping / Misdirected Request |
| 422 | Unprocessable entity (WebDAV) |
| 423 | Locked (WebDAV) |
| 424 | Method failure (WebDAV) |
| 425 | Unordered Collection (WebDAV RFC 3648) |
| 426 | Upgrade Required (RFC 2817) |
| 428 | Precondition Required (RFC 6585) |
| 429 | Too Many Requests (RFC 6585) |
| 431 | Request Header Fields Too Large (RFC 6585) |
| 449 | Retry With (Microsoft) |
| 450 | Blocked by Windows Parental Controls (Microsoft) |
| 451 | Unavailable For Legal Reasons |
| 456 | Unrecoverable Error (WebDAV) |
| 444 | No Response (Nginx) |
| 495 | SSL Certificate Error (Nginx) |
| 496 | SSL Certificate Required (Nginx) |
| 497 | HTTP Request Sent to HTTPS Port (Nginx) |
| 498 | Token expired/invalid (Nginx) |
| 499 | Client Closed Request (Nginx) |
| Server Error 5xx |
| 500 | Internal Server Error |
| 501 | Not Implemented |
| 502 | Bad Gateway / Proxy Error |
| 503 | Service Unavailable |
| 504 | Gateway Timeout |
| 505 | HTTP Version Not Supported |
| 506 | Variant Also Negotiates (RFC 2295) |
| 507 | Insufficient storage (WebDAV) |
| 508 | Loop detected (WebDAV RFC 5842) |
| 509 | Bandwidth Limit Exceeded |
| 510 | Not extended (RFC 2774) |
| 511 | Network authentication required (RFC 6585) |
| 520 | Unknown Error (Cloudflare) |
| 521 | Web Server Is Down (Cloudflare) |
| 522 | Connection Timed Out (Cloudflare) |
| 523 | Origin Is Unreachable (Cloudflare) |
| 524 | A Timeout Occurred (Cloudflare) |
| 525 | SSL Handshake Failed (Cloudflare) |
| 526 | Invalid SSL Certificate (Cloudflare) |
| 527 | Railgun Error (Cloudflare) |