按名稱或代碼搜尋，查找所有 HTTP 狀態碼。包含說明、範例和最佳實踐。
60 個狀態碼
The server has received the request headers and the client should proceed to send the request body.
使用場景： Large file uploads — client sends Expect: 100-continue before body.
The server agrees to switch protocols as requested by the client.
使用場景： WebSocket upgrades: HTTP → WebSocket.
The server has received and is processing the request, but no response is yet available.
使用場景： Long-running WebDAV operations to prevent client timeout.
Returns response headers before the final response, allowing the client to preload resources.
使用場景： Preloading critical CSS/JS while the server prepares the full response.
The request has succeeded. The response body contains the requested resource.
使用場景： Standard successful GET, POST, PUT, PATCH responses.
The request has been fulfilled and a new resource has been created.
使用場景： Successful POST that creates a resource. Include Location header pointing to new resource.
The request has been accepted for processing but processing has not been completed.
使用場景： Async operations: email sending, report generation, batch jobs.
The response is successful but the information was obtained from a third-party source.
使用場景： Proxies or mirrors that transform the original response.
The server successfully processed the request but returns no content.
使用場景： DELETE operations, form submissions with no redirect, successful PATCH with no body needed.
The server successfully processed the request and asks the client to reset the document view.
使用場景： Forms — server wants the client to clear the form after submission.
The server is delivering only part of the resource due to a range header sent by the client.
使用場景： Video streaming, resumable file downloads, pagination of large binary resources.
The response body contains status information for multiple independent operations.
使用場景： WebDAV batch operations where each sub-request has its own status.
Members of a DAV binding have already been enumerated in a previous reply.
使用場景： WebDAV — avoids re-listing resources already returned.
The server has fulfilled a GET for the resource and the response represents the result of one or more instance manipulations.
使用場景： HTTP delta encoding — differential responses for caching efficiency.
The request has more than one possible response. The user should choose one.
使用場景： Content negotiation — multiple formats or languages available.
The resource has been permanently moved to a new URL. Future requests should use the new URL.
使用場景： Site migration, domain changes. Passes full SEO link equity to new URL.
The resource is temporarily at a different URL. Client should continue using original URL.
使用場景： Temporary maintenance pages, A/B testing redirects.
The server directs the client to get the requested resource at another URI using a GET request.
使用場景： Post/Redirect/Get pattern — after a successful POST, redirect to a confirmation page.
The resource has not been modified since the last request. Client should use its cached version.
使用場景： Conditional GET with If-None-Match or If-Modified-Since. Saves bandwidth.
The resource is temporarily at a different URL. The method and body must not change.
使用場景： Like 302, but guarantees the HTTP method is preserved on redirect.
The resource has permanently moved. The method and body must not change.
使用場景： Like 301 but method-preserving. Good for migrating POST endpoints.
The server cannot process the request due to client error (malformed syntax, invalid parameters).
使用場景： Invalid JSON body, missing required fields, invalid query params, validation failures.
The client must authenticate itself to get the requested response.
使用場景： Missing or invalid Bearer token / API key. Should trigger a login prompt.
Reserved for future use; some APIs use it for subscription/paywall responses.
使用場景： Paywalled API endpoints, exceeded free-tier limits, subscription required.
The client is authenticated but lacks permission to access the resource.
使用場景： User is logged in but lacks the required role or ownership. Don't reveal resource existence.
The server cannot find the requested resource. The URL may be incorrect or the resource deleted.
使用場景： Missing pages, deleted resources, invalid IDs. Most common HTTP error.
The HTTP method is not supported for the requested resource.
使用場景： Calling DELETE on a read-only endpoint. Include Allow header listing valid methods.
The server cannot produce a response matching the Accept headers sent by the client.
使用場景： Client requests application/xml but only JSON is available.
The client must authenticate itself with the proxy server.
使用場景： Corporate proxy requiring credentials before passing requests through.
The server timed out waiting for the request.
使用場景： Client took too long to send the complete request. Server closes the connection.
The request conflicts with the current state of the server.
使用場景： Duplicate username registration, version conflicts in optimistic concurrency.
The resource is permanently deleted and will not be available again.
使用場景： Deleted content where you want search engines to deindex permanently.
The server requires a Content-Length header in the request.
使用場景： API endpoints that need to pre-allocate resources based on expected body size.
The server does not meet a precondition the client specified in its headers.
使用場景： Optimistic concurrency with If-Match/ETags. Edit conflict detection.
The request body is larger than the server is willing to process.
使用場景： File upload exceeds limit. Include Retry-After if temporary.
The URI provided was too long for the server to process.
使用場景： Excessively long query strings, typically from GET requests with too much data.
The media format of the request body is not supported by the server.
使用場景： Sending XML to an endpoint that only accepts JSON.
The range specified in the Range header cannot be fulfilled.
使用場景： File download resumed beyond the file's actual size.
The expectation indicated in the Expect header cannot be met by the server.
使用場景： Client sends Expect: 100-continue but server can't accommodate it.
The server refuses to brew coffee because it's a teapot (RFC 2324 April Fools' joke).
使用場景： Easter egg in APIs. Some services use it to reject clearly bot-driven requests.
The request was well-formed but failed semantic validation.
使用場景： JSON is valid but business logic validation fails (e.g., end date before start date).
The resource that is being accessed is locked.
使用場景： WebDAV — file checked out by another user.
The request failed because it depended on another request that failed.
使用場景： WebDAV batch operations where a prior step failed.
The server is unwilling to process a request that might be replayed.
使用場景： TLS 0-RTT early data that could be a replay attack.
The client should switch to a different protocol.
使用場景： Server requires HTTPS but received HTTP, or requires HTTP/2.
The server requires the request to be conditional to prevent lost updates.
使用場景： API requires If-Match header for update operations to prevent conflicts.
The user has sent too many requests in a given amount of time (rate limiting).
使用場景： API rate limits exceeded. Include Retry-After header with wait time.
The server is unwilling to process the request because its header fields are too large.
使用場景： Excessively large cookies or too many custom headers.
The resource is unavailable due to legal reasons such as government censorship.
使用場景： GDPR compliance blocking, DMCA takedowns, regional legal restrictions.
The server encountered an unexpected condition that prevented it from fulfilling the request.
使用場景： Unhandled exceptions, database errors, configuration issues. Generic catch-all.
The server does not support the functionality required to fulfill the request.
使用場景： HTTP method not recognized or not yet implemented by the server.
The server, while acting as a gateway, received an invalid response from the upstream server.
使用場景： Upstream API timeout, crashed microservice behind load balancer.
The server is temporarily unable to handle the request due to overload or maintenance.
使用場景： Planned maintenance, server overload. Include Retry-After header.
The server, acting as a gateway, did not receive a timely response from the upstream server.
使用場景： Slow database queries, slow microservices causing proxy timeouts.
The HTTP protocol version used in the request is not supported by the server.
使用場景： Rare — client uses an unsupported HTTP version.
The server has an internal configuration error with transparent content negotiation.
使用場景： Circular reference in content negotiation configuration.
The server is unable to store the representation needed to complete the request.
使用場景： WebDAV — disk full. Also used in some APIs for quota exhaustion.
The server detected an infinite loop while processing the request.
使用場景： WebDAV — infinite loop in directory binding.
Further extensions to the request are required for the server to fulfill it.
使用場景： HTTP Extension Framework — specific extension policy not met.
The client needs to authenticate to gain network access.
使用場景： Captive portals — hotel/airport Wi-Fi login pages.
HTTP 狀態碼是 Web 伺服器回應用戶端請求時返回的 3 位數字。它們表明請求是否成功、被重新導向或遇到錯誤。第一位數字定義回應類別：1xx（資訊）、2xx（成功）、3xx（重新導向）、4xx（用戶端錯誤）、5xx（伺服器錯誤）。
301（永久移動）告知瀏覽器和搜尋引擎頁面已永久移動至新 URL，將完整的 SEO 連結權重傳遞給新 URL。302（發現 / 臨時重新導向）表示臨時移動；瀏覽器會重新導向，但搜尋引擎通常保留原始 URL 的索引。
401 Unauthorized 表示用戶端未經身份驗證 — 未提供憑證或憑證無效。403 Forbidden 表示用戶端已通過身份驗證，但無權存取該資源。需要提示使用者登入時使用 401，使用者已登入但缺少權限時使用 403。
對於建立資源的成功 POST，返回 201 Created 並附帶指向新資源的 Location 標頭。對於觸發處理但不建立資源的成功 POST，返回 200 OK。對於處理尚未完成的非同步操作，返回 202 Accepted。