HTTP 상태 코드 참조
개발
모든 HTTP 상태 코드를 카테고리별(정보 1xx, 성공 2xx, 리다이렉트 3xx, 클라이언트 오류 4xx, 서버 오류 5xx)로 묶은 검색 가능한 치트시트. 코드(404), 이름(Not Found), 설명의 키워드(cache, timeout) 어떤 것으로든 검색 가능합니다. 카드마다 한 줄 의미와 복사 버튼이 있어 PR 코멘트나 커밋 메시지에 쉽게 가져다 쓸 수 있습니다.
- 100Continue
The initial part of the request has been received and the client should continue sending the rest.
- 101Switching Protocols
The server is switching protocols as requested in the Upgrade header (e.g., to WebSocket).
- 102Processing
The server has received and is processing the request, but no response is available yet (WebDAV).
- 103Early Hints
Used to preload resources while the server prepares the final response.
- 200OK
The request succeeded. The meaning depends on the HTTP method used.
- 201Created
The request succeeded and a new resource was created — typically returned after POST.
- 202Accepted
The request was accepted for processing, but the processing has not been completed.
- 204No Content
The request succeeded but no body is returned — common for PUT or DELETE.
- 205Reset Content
Tells the client to reset the view that sent the request (e.g., clear a form).
- 206Partial Content
Returned when the client used the Range header to request a portion of the resource.
- 207Multi-Status
WebDAV — multiple resources, each with its own status code, returned inside an XML body.
- 301Moved Permanently
The resource has a new permanent URL. Search engines update their index to the new location.
- 302Found
The resource is temporarily at a different URL — client should keep using the original URL for future requests.
- 303See Other
After a POST, redirect the client to GET another resource (PRG pattern).
- 304Not Modified
The cached version is still fresh — the client should use its cache.
- 307Temporary Redirect
Like 302, but the request method must not change on the redirect.
- 308Permanent Redirect
Like 301, but the request method must not change on the redirect.
- 400Bad Request
The server cannot process the request due to a client-side error (malformed syntax, missing required fields).
- 401Unauthorized
Authentication is required and either missing or invalid. The response should include a WWW-Authenticate header.
- 402Payment Required
Reserved for future use — sometimes used by APIs to indicate billing-related failures.
- 403Forbidden
The server understood the request but refuses to authorize it. Authentication will not help.
- 404Not Found
The requested resource does not exist on the server.
- 405Method Not Allowed
The HTTP method is not supported for this resource (e.g., POST to a read-only endpoint).
- 406Not Acceptable
The server cannot return a response matching the Accept headers from the request.
- 407Proxy Authentication Required
Authentication with a proxy is required to access the resource.
- 408Request Timeout
The server did not receive a complete request within its idle timeout.
- 409Conflict
The request conflicts with the current state of the resource (e.g., concurrent edits).
- 410Gone
The resource is permanently gone — stronger than 404; tells caches and search engines to drop it.
- 411Length Required
The request did not specify a Content-Length, which this server requires.
- 412Precondition Failed
A condition in the request headers (e.g., If-Match) was not met.
- 413Payload Too Large
The request body is larger than the server is willing to process.
- 414URI Too Long
The URI is longer than the server is willing to interpret.
- 415Unsupported Media Type
The Content-Type of the request is not supported by the server.
- 416Range Not Satisfiable
The Range header cannot be fulfilled (out of the resource bounds).
- 417Expectation Failed
The Expect header could not be fulfilled by the server.
- 418I'm a teapot
An April Fools joke from RFC 2324 — used as an Easter egg in some APIs.
- 422Unprocessable Entity
The request is syntactically correct but semantically wrong (failed validation). Common in REST APIs.
- 423Locked
WebDAV — the resource is locked.
- 424Failed Dependency
WebDAV — the request failed because a previous request it depended on failed.
- 425Too Early
The server is unwilling to risk processing a request that may be replayed.
- 426Upgrade Required
The client should upgrade to a different protocol (e.g., TLS).
- 428Precondition Required
The server requires the request to be conditional (e.g., If-Match).
- 429Too Many Requests
The client has sent too many requests in a given time — rate limited. Look for Retry-After.
- 431Request Header Fields Too Large
The request headers are too large in total or individually.
- 451Unavailable For Legal Reasons
The resource is blocked due to a legal demand (named after Ray Bradbury's Fahrenheit 451).
- 500Internal Server Error
A generic server error — something failed and the server has no more specific message.
- 501Not Implemented
The server does not support the functionality required to fulfill the request.
- 502Bad Gateway
Acting as a gateway / proxy, the server got an invalid response from an upstream server.
- 503Service Unavailable
The server is temporarily unable to handle requests — overloaded or down for maintenance.
- 504Gateway Timeout
Acting as a gateway / proxy, the server did not get a response from an upstream server in time.
- 505HTTP Version Not Supported
The HTTP version in the request is not supported by the server.
- 507Insufficient Storage
WebDAV — the server cannot store the representation needed to complete the request.
- 508Loop Detected
WebDAV — the server detected an infinite loop while processing the request.
- 511Network Authentication Required
The client must authenticate to gain network access (used by captive portals).
사용법
- 색상 칩으로 카테고리를 필터링하세요.
- 검색창에 코드·이름·설명 키워드를 입력하세요.
- 제목 옆 버튼으로 상태 코드를 복사하세요.
자주 묻는 질문
- 1xx 코드는 왜 중요한가요?
- 직접 보는 경우는 드물지만 고급 시나리오에 유용 — 100 Continue로 큰 업로드 전에 서버 수락을 확인하고, 103 Early Hints로 브라우저가 응답 준비 동안 리소스를 미리 로드할 수 있습니다.
- 301과 308 차이?
- 둘 다 '영구 이동'. 301은 리다이렉트 시 HTTP 메서드 변경을 허용(대부분 POST → GET). 308은 메서드 유지 강제. API 리다이렉트엔 308, 레거시 웹엔 301.
- 422 vs 400은 언제?
- 400은 요청 자체가 잘못된 경우(잘못된 JSON, 누락된 헤더). 422는 문법은 맞지만 의미가 틀린 경우(예: email 필드에 문자열이 있지만 유효한 이메일이 아님).
- 418 'I'm a teapot'은?
- RFC 2324(HTCPCP — 하이퍼텍스트 커피포트 제어 프로토콜)의 만우절 농담. 일부 API가 부활절 달걀이나 '의도적 미구현' 신호로 사용.
관련 도구
JWT 디코더
JWT의 헤더·클레임·만료를 즉시 확인하세요.
UUID 생성기
무작위 버전4 UUID를 여러 개 한 번에 생성하고 복사하세요.
해시 생성기 (SHA)
텍스트로 SHA-1·SHA-256·SHA-384·SHA-512 해시를 생성하세요.
URL 인코더 / 디코더
URL용으로 텍스트를 퍼센트 인코딩하거나, 인코딩된 URL을 디코딩하세요.
Base64 인코더 / 디코더
텍스트를 Base64로 인코딩하거나 다시 텍스트로 디코딩하세요.
JSON 포맷터 & 검증기
브라우저에서 바로 JSON을 포맷·정렬·압축·검증하세요.