Códigos de estado HTTP
Busca por número o por nombre para saber qué significa un código de estado y cuándo debe enviarlo un servidor.
1xx · Informativo
- 100ContinueThe request headers were received; the client may send the body. · RFC 9110
- 101Switching ProtocolsThe server agrees to switch to the protocol named in Upgrade. · RFC 9110
- 102ProcessingThe server has accepted the request but has not finished it yet. · RFC 2518
- 103Early HintsPreliminary headers, usually Link, sent before the final response. · RFC 8297
2xx · Éxito
- 200OKThe request succeeded. · RFC 9110
- 201CreatedA new resource was created; Location points to it. · RFC 9110
- 202AcceptedThe request was accepted for processing, but is not complete. · RFC 9110
- 203Non-Authoritative InformationThe response was modified by a proxy. · RFC 9110
- 204No ContentSuccess with no body to return. · RFC 9110
- 205Reset ContentSuccess; the client should reset the document view. · RFC 9110
- 206Partial ContentOnly the requested byte range is returned. · RFC 9110
- 207Multi-StatusWebDAV: multiple status codes in the XML body. · RFC 4918
- 208Already ReportedWebDAV: members were already listed earlier in the response. · RFC 5842
- 226IM UsedThe response is a delta of the resource. · RFC 3229
3xx · Redirección
- 300Multiple ChoicesSeveral representations exist; the client should pick one. · RFC 9110
- 301Moved PermanentlyThe resource has a new permanent URL; search engines update their index. · RFC 9110
- 302FoundTemporary redirect; the method may change to GET. · RFC 9110
- 303See OtherRedirect to another resource with GET, typically after a POST. · RFC 9110
- 304Not ModifiedThe cached copy is still valid; no body is sent. · RFC 9110
- 307Temporary RedirectTemporary redirect that keeps the method and body. · RFC 9110
- 308Permanent RedirectPermanent redirect that keeps the method and body. · RFC 9110
4xx · Error del cliente
- 400Bad RequestThe request is malformed or invalid. · RFC 9110
- 401UnauthorizedAuthentication is required or failed. · RFC 9110
- 402Payment RequiredReserved; used by some APIs for billing problems. · RFC 9110
- 403ForbiddenThe server understood the request but refuses to authorise it. · RFC 9110
- 404Not FoundNo resource exists at this URL. · RFC 9110
- 405Method Not AllowedThe HTTP method is not supported for this resource. · RFC 9110
- 406Not AcceptableNo representation matches the Accept headers. · RFC 9110
- 407Proxy Authentication RequiredThe client must authenticate with the proxy first. · RFC 9110
- 408Request TimeoutThe server gave up waiting for the request. · RFC 9110
- 409ConflictThe request conflicts with the current state, e.g. an edit collision. · RFC 9110
- 410GoneThe resource was removed permanently. · RFC 9110
- 411Length RequiredContent-Length is missing. · RFC 9110
- 412Precondition FailedAn If-* precondition was not met. · RFC 9110
- 413Content Too LargeThe request body exceeds the server's limit. · RFC 9110
- 414URI Too LongThe URL is longer than the server accepts. · RFC 9110
- 415Unsupported Media TypeThe body format is not supported. · RFC 9110
- 416Range Not SatisfiableThe requested byte range is outside the resource. · RFC 9110
- 417Expectation FailedThe Expect header could not be met. · RFC 9110
- 418I'm a teapotApril Fools' joke from RFC 2324; teapots refuse to brew coffee. · RFC 2324
- 421Misdirected RequestThe request was sent to a server that cannot answer for this origin. · RFC 9110
- 422Unprocessable ContentThe syntax is fine but the content fails validation. · RFC 9110
- 423LockedWebDAV: the resource is locked. · RFC 4918
- 424Failed DependencyWebDAV: an earlier request in the batch failed. · RFC 4918
- 425Too EarlyThe server refuses to risk a replayed request. · RFC 8470
- 426Upgrade RequiredThe client must switch protocols, e.g. to TLS. · RFC 9110
- 428Precondition RequiredThe request must be conditional to avoid lost updates. · RFC 6585
- 429Too Many RequestsRate limit hit; Retry-After says when to try again. · RFC 6585
- 431Request Header Fields Too LargeHeaders are too big, often oversized cookies. · RFC 6585
- 451Unavailable For Legal ReasonsBlocked by a legal demand, such as a court order. · RFC 7725
5xx · Error del servidor
- 500Internal Server ErrorThe server hit an unexpected error. · RFC 9110
- 501Not ImplementedThe server does not support the request method. · RFC 9110
- 502Bad GatewayAn upstream server returned an invalid response. · RFC 9110
- 503Service UnavailableThe server is overloaded or down for maintenance. · RFC 9110
- 504Gateway TimeoutAn upstream server did not answer in time. · RFC 9110
- 505HTTP Version Not SupportedThe HTTP version in the request is not supported. · RFC 9110
- 506Variant Also NegotiatesContent negotiation is misconfigured on the server. · RFC 2295
- 507Insufficient StorageWebDAV: the server is out of space. · RFC 4918
- 508Loop DetectedWebDAV: infinite loop while processing. · RFC 5842
- 510Not ExtendedFurther extensions are required. · RFC 2774
- 511Network Authentication RequiredA captive portal requires login before network access. · RFC 6585
Sobre esta herramienta
Toda respuesta HTTP empieza con un estado de tres dígitos. El primer dígito indica la clase: 1xx informativo, 2xx éxito, 3xx redirección, 4xx el cliente hizo algo mal, 5xx el servidor falló. Conocer el código exacto importa para el SEO (301 frente a 302 decide si los buscadores actualizan su índice), para el diseño de APIs (422 frente a 400, 401 frente a 403) y para depurar (502 y 504 apuntan a un servicio superior, 503 a una sobrecarga).
Esta lista sigue el RFC 9110, la especificación vigente de la semántica de HTTP, más los códigos registrados en los RFC de WebDAV, limitación de peticiones y bloqueo legal. Cada entrada incluye una explicación de una línea sobre lo que comunica el código y el RFC que lo define.
Preguntas frecuentes
- ¿Cuál es la diferencia entre 401 y 403?
- 401 significa que no estás autenticado: inicia sesión y vuelve a intentarlo. 403 significa que se te reconoce pero no tienes permiso; volver a iniciar sesión no servirá de nada.
- ¿301 o 308 para una redirección permanente?
- Ambas son permanentes. 308 garantiza que se conservan el método y el cuerpo; 301 puede convertirse en un GET según el cliente.
- ¿El 418 existe de verdad?
- Viene de un RFC del Día de los Inocentes y no forma parte del estándar HTTP, pero muchos servidores lo implementan por diversión.