HTTP Status Code Lookup
Search HTTP status codes by number or words and see what each means and what to do.
| Code | Name | What it means | What to do |
|---|---|---|---|
| 100 | Continue | The server has received the request headers and the client should send the body. | Normally handled automatically by the client. |
| 101 | Switching Protocols | The server agrees to switch protocol, for example to WebSocket. | Expected when upgrading a connection. |
| 102 | Processing | The server has accepted the request and is still working on it (WebDAV). | Wait; a final status will follow. |
| 103 | Early Hints | Headers sent early so the browser can start loading resources. | Used for preloading; no action needed. |
| 200 | OK | The request succeeded. | Nothing to fix. |
| 201 | Created | The request succeeded and a new resource was created. | Common after a POST that creates something. |
| 202 | Accepted | The request was accepted for processing but is not finished. | Check back later for the result. |
| 203 | Non-Authoritative Information | The request succeeded but a proxy changed the response. | Rare; usually harmless. |
| 204 | No Content | The request succeeded and there is nothing to return. | Normal for deletes and some updates. |
| 205 | Reset Content | The request succeeded; the client should reset the form or view. | Rare. |
| 206 | Partial Content | Only part of the resource is returned, as asked by a Range header. | Normal for video seeking and resumed downloads. |
| 207 | Multi-Status | Several results in one response (WebDAV). | Read each part of the body. |
| 208 | Already Reported | Members were already listed earlier in the response (WebDAV). | Rare. |
| 226 | IM Used | The response is the result of one or more instance manipulations. | Rare. |
| 300 | Multiple Choices | There are several possible responses and the client must choose. | Rare; offer a clear link instead. |
| 301 | Moved Permanently | The resource has a new permanent address. | Update links; search engines pass ranking signals to the new URL. |
| 302 | Found | The resource is temporarily at another address. | Use for short-term moves; search engines keep the old URL. |
| 303 | See Other | Get the result from another URL using GET. | Common after a form POST. |
| 304 | Not Modified | The cached copy is still current. | Normal caching behaviour. |
| 305 | Use Proxy | Use the given proxy (deprecated). | Do not use. |
| 307 | Temporary Redirect | Temporary redirect that keeps the same method. | Use instead of 302 when the method must not change. |
| 308 | Permanent Redirect | Permanent redirect that keeps the same method. | Use instead of 301 when the method must not change. |
| 400 | Bad Request | The server could not understand the request because it is malformed. | Check the syntax, parameters and body. |
| 401 | Unauthorized | Authentication is required or has failed. | Send valid credentials or log in. |
| 402 | Payment Required | Reserved for future use; some services use it for billing limits. | Check the service's documentation. |
| 403 | Forbidden | The server understood the request but refuses it. | Check permissions; logging in will not help if you lack rights. |
| 404 | Not Found | The resource does not exist at this address. | Check the URL; add a redirect if the page moved. |
| 405 | Method Not Allowed | The method (GET, POST...) is not allowed for this resource. | Use a method listed in the Allow header. |
| 406 | Not Acceptable | The server cannot produce a response matching the Accept headers. | Relax the Accept headers. |
| 407 | Proxy Authentication Required | Authenticate with the proxy first. | Provide proxy credentials. |
| 408 | Request Timeout | The server timed out waiting for the request. | Retry; check the connection. |
| 409 | Conflict | The request conflicts with the current state of the resource. | Resolve the conflict, such as a version clash, and retry. |
| 410 | Gone | The resource was removed on purpose and will not return. | Remove links; search engines drop it sooner than a 404. |
| 411 | Length Required | A Content-Length header is required. | Add the header. |
| 412 | Precondition Failed | A condition in the request headers was not met. | Re-fetch and retry with current values. |
| 413 | Content Too Large | The request body is larger than the server allows. | Send less data or raise the server limit. |
| 414 | URI Too Long | The URL is longer than the server will accept. | Shorten it or use POST. |
| 415 | Unsupported Media Type | The body format is not supported. | Check the Content-Type header. |
| 416 | Range Not Satisfiable | The requested byte range cannot be served. | Request a valid range. |
| 417 | Expectation Failed | The server cannot meet the Expect header. | Remove the Expect header. |
| 418 | I'm a teapot | A joke status from an April Fools' RFC; a teapot refuses to brew coffee. | Sometimes used deliberately; not a real error. |
| 421 | Misdirected Request | The request was sent to a server that cannot answer it. | Check the host and connection reuse. |
| 422 | Unprocessable Content | The request is well formed but its content is invalid. | Fix the validation errors in the body. |
| 423 | Locked | The resource is locked (WebDAV). | Unlock it or wait. |
| 424 | Failed Dependency | The request failed because an earlier one failed (WebDAV). | Fix the earlier request. |
| 425 | Too Early | The server will not risk processing a replayable request. | Retry after the handshake completes. |
| 426 | Upgrade Required | The client must switch to another protocol. | Follow the Upgrade header. |
| 428 | Precondition Required | The server requires a conditional request. | Add If-Match or similar. |
| 429 | Too Many Requests | You are being rate limited. | Slow down and respect the Retry-After header. |
| 431 | Request Header Fields Too Large | The headers are too large. | Reduce cookies and header size. |
| 451 | Unavailable For Legal Reasons | Access is denied for legal reasons. | Nothing you can fix client-side. |
| 500 | Internal Server Error | The server hit an unexpected problem. | Check the server logs; it is not the client's fault. |
| 501 | Not Implemented | The server does not support the requested method. | Use a supported method. |
| 502 | Bad Gateway | A gateway or proxy got an invalid response from the server behind it. | Check the upstream server and retry. |
| 503 | Service Unavailable | The server is overloaded or down for maintenance. | Retry later; send Retry-After. Search engines treat it as temporary. |
| 504 | Gateway Timeout | A gateway or proxy timed out waiting for the server behind it. | Check the upstream server speed and timeouts. |
| 505 | HTTP Version Not Supported | The HTTP version used is not supported. | Use a supported version. |
| 506 | Variant Also Negotiates | A configuration error in content negotiation. | Fix the server configuration. |
| 507 | Insufficient Storage | The server cannot store what is needed (WebDAV). | Free space on the server. |
| 508 | Loop Detected | The server detected an infinite loop (WebDAV). | Fix the circular reference. |
| 510 | Not Extended | Further extensions are required (rare). | Check the extension policy. |
| 511 | Network Authentication Required | You must authenticate to use the network, as on a captive portal. | Log in to the network. |
What this tool does
HTTP status codes are three-digit numbers a server returns to say how a request went: 2xx means success, 3xx a redirect, 4xx a client error and 5xx a server error. Type a code or a word such as redirect or timeout into the search box to see what the code means and what to do about it, and filter by class.
Lists the HTTP status codes in common use with their name, meaning and practical advice.
Filters by search words or by class and exports the visible rows.
How to use it
- Type a code or words such as 404, redirect or timeout.
- Optionally pick a class, such as 4xx.
- Read the meaning and the suggestion for each match.
- Press Copy results or Download CSV.
Why use this reference
Searchable list of HTTP status codes by number or plain words, with what each means and what to do about it. Error numbers appear in browsers, logs, APIs and monitoring tools with little explanation. A quick lookup tells you whether a 301, a 403 or a 503 is your problem or the server's, and what to try next.
Why we built it
We built the HTTP status code lookup to include a plain "what to do" for each code and a class filter. Set up redirects with the redirect generator and parse a request URL with the URL parser.
Who this tool is for
- Developers debugging responses
- SEO staff diagnosing redirects and errors
- Support teams reading logs
When to use it
- Debugging a failing API request or a broken link.
- Setting up redirects and choosing between 301 and 302.
- Reading a server log or a monitoring alert.
- Learning what each class of code means.
How it works
The first digit gives the class: 1xx informational, 2xx success, 3xx redirection, 4xx client error and 5xx server error. The meanings follow the HTTP semantics specification (RFC 9110) and common extensions; the "what to do" column is practical guidance rather than part of the standard.
A 4xx code means the request is the problem; a 5xx code means the server could not complete a valid request.
What you give it, and what you get back
| Item | Details |
|---|---|
| Search | A code number or words from the name or description. |
| Class | Optional filter: 1xx, 2xx, 3xx, 4xx or 5xx. |
| Result | Code, name, meaning and suggested action for each match. |
| Export | Copy as text or download as CSV. |
Issues you may run into
| What you see | Why it happens | What to do |
|---|---|---|
| A code is not listed | Only codes in common use are included. | Check the service's own documentation for custom codes. |
| Nothing matches | The words do not appear in the descriptions. | Try the number or a simpler word. |
| Advice does not fit my case | The suggestions are general. | Check server logs and documentation for specifics. |
Assumptions and limitations
- Covers the codes in common use rather than every registered code.
- Suggestions are general guidance, not a diagnosis of your server.
Frequently asked questions
What does a 404 status code mean?
The server could not find the page at that address, either because it was removed, moved or mistyped.
What is the difference between 301 and 302?
A 301 is a permanent move that passes ranking signals to the new address. A 302 is temporary, so search engines keep the old address.
What is the difference between 401 and 403?
401 means authentication is missing or failed. 403 means the server understood you but refuses access.
What does 500 mean?
An unexpected error on the server. Check server logs; the visitor cannot fix it.
What does 429 mean?
Too many requests: you are being rate limited. Slow down and wait for the time given in Retry-After.
Is it free and private?
Yes. It is a static list that runs in your browser.
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