Referência de Códigos de Status HTTP

Referência de Códigos de Status HTTP

Referência completa de códigos de status HTTP — todos os códigos 1xx, 2xx, 3xx, 4xx e 5xx explicados com significados, casos de uso e impacto no SEO.

Atualizado em maio de 2026

100 INFO

Continue

The server has received the request headers and the client should proceed to send the request body.

101 INFO

Switching Protocols

The server agrees to switch protocols as requested by the client via the Upgrade header.

102 INFO

Processing

The server has received and is processing the request, but no response is available yet.

103 INFO

Early Hints

Used to return response headers before the final HTTP message, allowing the browser to start preloading resources.

200 SUCCESS

OK

The request succeeded. The server returned the requested resource. Required for a page to be indexed by Google.

201 SUCCESS

Created

The request succeeded and a new resource was created. Commonly used in REST APIs after a POST request.

202 SUCCESS

Accepted

The request has been accepted for processing, but processing has not been completed yet.

203 SUCCESS

Non-Authoritative Information

The request succeeded but the returned metadata is from a local or third-party copy, not the origin server.

204 SUCCESS

No Content

The request succeeded but there is no content to return. Common for DELETE or PATCH API responses.

205 SUCCESS

Reset Content

The server fulfilled the request and asks the client to reset the document view (e.g., clear a form).

206 SUCCESS

Partial Content

The server is delivering only part of the resource due to a Range header. Used in streaming and resumable downloads.

207 SUCCESS

Multi-Status

Conveys information about multiple resources in situations where multiple status codes might be appropriate. Used in WebDAV.

208 SUCCESS

Already Reported

The members of a DAV binding have already been enumerated in a preceding part of the response.

226 SUCCESS

IM Used

The server fulfilled a GET request and the response is a representation of the result of one or more instance-manipulations.

300 REDIRECT

Multiple Choices

The request has more than one possible response. The user agent or user should choose one.

301 REDIRECT

Moved Permanently

The resource has permanently moved to a new URL. Passes full link equity — use for all permanent redirects and HTTPS migrations.

302 REDIRECT

Found

The resource has temporarily moved. Google passes signals through 302s but use 301 for permanent moves to avoid canonical confusion.

303 REDIRECT

See Other

The server redirects the client to a different resource using a GET request. Often used after a POST to prevent form resubmission.

304 REDIRECT

Not Modified

The resource has not changed since the last request. The browser should use its cached version. Reduces bandwidth on repeat visits.

307 REDIRECT

Temporary Redirect

Like 302, but explicitly preserves the HTTP method. Use when method preservation is required for temporary redirects.

308 REDIRECT

Permanent Redirect

Like 301, but preserves the HTTP method. Used in APIs that need to permanently redirect POST requests.

400 CLIENT ERROR

Bad Request

The server cannot process the request due to malformed syntax or invalid parameters. Common in APIs with missing or invalid fields.

401 CLIENT ERROR

Unauthorized

Authentication is required and has not been provided or is invalid. Means "Who are you?" — not to be confused with 403.

402 CLIENT ERROR

Payment Required

Reserved for future use. Originally intended for digital payment systems; now used by some APIs to signal quota limits.

403 CLIENT ERROR

Forbidden

The server understood the request but refuses to authorize it. The client is known but lacks permission. Distinct from 401.

404 CLIENT ERROR

Not Found

The server cannot find the requested resource. The most common error on the web. Redirect important 404 pages with a 301.

405 CLIENT ERROR

Method Not Allowed

The HTTP method used is not allowed for the requested resource. The response must include an Allow header listing valid methods.

406 CLIENT ERROR

Not Acceptable

The server cannot produce a response matching the list of acceptable values in the request's Accept headers.

407 CLIENT ERROR

Proxy Authentication Required

Authentication with the proxy server is required before the request can be fulfilled.

408 CLIENT ERROR

Request Timeout

The server timed out waiting for the request. The client may repeat the request without modifications.

409 CLIENT ERROR

Conflict

The request conflicts with the current state of the target resource. Common when trying to create a duplicate record.

410 CLIENT ERROR

Gone

The resource is permanently removed and will not return. Stronger removal signal than 404 — Google processes 410 faster for URL de-indexing.

411 CLIENT ERROR

Length Required

The server refuses to accept the request without a defined Content-Length header.

412 CLIENT ERROR

Precondition Failed

The server does not meet one or more preconditions set in the request headers.

413 CLIENT ERROR

Content Too Large

The request body is larger than the server is willing to process. The server may close the connection.

414 CLIENT ERROR

URI Too Long

The URI requested by the client is longer than the server is willing to interpret.

415 CLIENT ERROR

Unsupported Media Type

The media format of the requested data is not supported by the server. Check the Content-Type header.

416 CLIENT ERROR

Range Not Satisfiable

The server cannot serve the requested ranges. The Range header field value is outside the resource's actual size.

417 CLIENT ERROR

Expectation Failed

The server cannot meet the expectations indicated by the Expect request-header field.

418 CLIENT ERROR

I'm a Teapot

The server refuses to brew coffee because it is, permanently, a teapot. An April Fools' joke from RFC 2324 (1998), now a web easter egg.

421 CLIENT ERROR

Misdirected Request

The request was directed at a server that is not able to produce a response for the combination of scheme and authority.

422 CLIENT ERROR

Unprocessable Content

The request is syntactically valid but semantically incorrect. Common in REST APIs with strict field validation.

423 CLIENT ERROR

Locked

The resource being accessed is locked. Used in WebDAV to indicate the resource is locked.

424 CLIENT ERROR

Failed Dependency

The request failed because it depended on another request that failed. Used in WebDAV.

425 CLIENT ERROR

Too Early

The server is unwilling to risk processing a request that might be replayed, to prevent replay attacks.

426 CLIENT ERROR

Upgrade Required

The client should switch to a different protocol. The server sends an Upgrade header indicating the required protocol.

428 CLIENT ERROR

Precondition Required

The origin server requires the request to be conditional. Prevents the "lost update" problem in REST APIs.

429 CLIENT ERROR

Too Many Requests

The client has sent too many requests in a given time (rate limiting). If Googlebot receives 429s, crawl budget is reduced.

431 CLIENT ERROR

Request Header Fields Too Large

The server refuses to process the request because its header fields are too large.

451 CLIENT ERROR

Unavailable For Legal Reasons

The server cannot legally provide the requested resource. Named after Fahrenheit 451. Used for censorship or legal blocks.

500 SERVER ERROR

Internal Server Error

A generic server-side failure. Persistent 500s cause Google to lower crawl frequency and may trigger de-indexing. Monitor in Search Console.

501 SERVER ERROR

Not Implemented

The server does not support the functionality required to fulfill the request. The method is not recognized or implemented.

502 SERVER ERROR

Bad Gateway

The server received an invalid response from an upstream server. Common with Nginx or Cloudflare when the app server crashes or is overloaded.

503 SERVER ERROR

Service Unavailable

The server is temporarily unavailable — overloaded or under maintenance. Include a Retry-After header to prevent Google de-indexing.

504 SERVER ERROR

Gateway Timeout

The gateway did not receive a timely response from the upstream server. Common when a database query or API call takes too long.

505 SERVER ERROR

HTTP Version Not Supported

The server does not support the HTTP version used in the request.

506 SERVER ERROR

Variant Also Negotiates

The server has an internal configuration error: the chosen variant resource is configured to engage in content negotiation itself.

507 SERVER ERROR

Insufficient Storage

The server cannot store the representation needed to complete the request. Used in WebDAV.

508 SERVER ERROR

Loop Detected

The server detected an infinite loop while processing the request. Used in WebDAV.

510 SERVER ERROR

Not Extended

Further extensions to the request are required for the server to fulfill it.

511 SERVER ERROR

Network Authentication Required

The client needs to authenticate to gain network access. Used by captive portals (hotel Wi-Fi, etc.) to intercept HTTP requests.

Como usar

Busque por código, palavra-chave ou classe

1. Busque o código

Digite o número (404, 502) ou uma palavra-chave ("redirecionamento", "não autorizado").

2. Ou filtre por classe

Use os botões 1xx–5xx para navegar por categoria.

3. Leia significado e impacto no SEO

Cada código traz definição, caso de uso e nota prática para APIs e rastreamento.

O que esta ferramenta faz

Referência completa com foco prático

Todas as classes 1xx–5xx

Significado de cada código, não só uma lista — com contexto de quando usar.

Impacto no SEO explicado

Como cada código afeta rastreamento e indexação pelo Googlebot.

Notas para APIs REST

Quando usar 201 vs 204, como 429 afeta rate limiting, e mais.

Busca instantânea

Por número ou palavra-chave, sem precisar rolar a lista inteira.

Atalho de teclado para busca

Pressione Shift+K (ou Ctrl+K) em qualquer parte da página para focar o campo de busca sem tirar a mão do teclado.

Destaque para os códigos mais importantes

Um indicador visual marca os códigos mais encontrados no dia a dia (200, 301, 404, 429, 500 etc.), facilitando escanear a lista sem ler card por card.

Classes de status HTTP

Classe
Significado
1xx (100–199)
Informacional — raro para crawlers; usado em Early Hints (103) e troca de protocolo
2xx (200–299)
Sucesso — 200 obrigatório para indexação
3xx (300–399)
Redirecionamento — 301 passa link equity, 302 não consolida
4xx (400–499)
Erro do cliente — 404/410 removem páginas do índice
5xx (500–599)
Erro do servidor — persistente reduz rastreamento

Quando você vai usar isso

Os cenários mais comuns entre quem usa a ferramenta

Depurar um 502 bad gateway

Entenda que o servidor recebeu resposta inválida de um upstream — comum após deploy com falha.

Decidir entre redirect 301 ou 302

301 para mudanças permanentes que consolidam ranking; 302 para testes A/B e promoções temporárias.

Projetar respostas de API REST

Escolha o código certo — 201 para criação, 204 para sucesso sem corpo, 429 para rate limit.

Investigar quedas de indexação

Identifique se um "soft 404" ou 5xx persistente está causando desindexação no Search Console.

Entender um código inesperado de API externa

Recebeu um status que não reconhece de um webhook, gateway de pagamento ou serviço de terceiros? Busque pelo número e descubra o que ele significa antes de decidir como tratar a resposta.

Estudar para entrevista técnica ou certificação

Revise as classes e os códigos mais cobrados em provas e entrevistas de desenvolvimento web, com busca instantânea para tirar dúvidas pontuais.

Erro comum? Comece por aqui

Soft 404 — página retorna 200 mas está vazia

O Google trata como página ausente, desperdiçando crawl budget. Retorne 404/410 real.

Confundir 401 com 403

401 = "Quem é você?" (falta autenticação). 403 = "Sei quem você é, mas não pode entrar."

Manter 302 por longo prazo

Cria ambiguidade de canonical e impede o Google de atualizar o índice — use 301 para mudanças permanentes.

Retornar 200 OK em respostas de erro de API

Algumas APIs sempre respondem 200 e colocam o erro só no corpo JSON. Isso quebra o tratamento automático de erro no cliente, o monitoramento e o cache — use o código HTTP correto (4xx/5xx) junto com o corpo.

Encadear vários redirects 301 em sequência

Cada salto extra (301 → 301 → 301) atrasa o rastreamento e pode diluir parte do link equity. Aponte o redirecionamento direto para o destino final.

Esquecer o cabeçalho Retry-After em respostas 503

Sem ele, o Google não sabe quando tentar de novo, e um 503 persistente pode virar sinal de desindexação. Sempre inclua um Retry-After com um tempo realista.

Por que usar esta ferramenta

Não é só uma lista — cada código traz significado, caso de uso prático e impacto específico no SEO, útil tanto para devs depurando uma API quanto para SEOs investigando quedas de indexação.

A busca por palavra-chave e os filtros por classe tornam mais rápido achar o código certo do que rolar uma tabela gigante.

A cobertura vai além dos códigos do dia a dia: inclui também os menos conhecidos, como a família WebDAV (207, 423, 507), o 425 Too Early, o 451 Unavailable For Legal Reasons e até a piada de 1998 do 418 I'm a Teapot — tudo com busca instantânea e atalho de teclado (Shift+K) para quem consulta a referência com frequência.

301 vs. 302 — quando usar cada um

Permanente vs. temporário

301 Moved Permanently
302 Found
Consolida link equity
sim, completo
sim, na implementação atual do Google
Cache do navegador
agressivo
não armazenado em cache
Use para
migração HTTPS, mudança de domínio
teste A/B, promoção sazonal, geo-redirect

Perguntas frequentes

Ambos indicam página indisponível. 404 significa que o recurso não foi encontrado — pode existir de novo no futuro. 410 declara remoção permanente. O Google processa o 410 mais rapidamente para remoção do índice.

Referências

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