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Look Up an HTTP Status Code
Http Status Code Lookup for quick browser-based work with focused input and copy-ready output.
Showing 62 of 62 entries.
1xx Informational
| Code | Name | Meaning |
|---|---|---|
| 100 | Continue | The server received the request headers; the client should send the body. |
| 101 | Switching Protocols | The server agrees to switch protocols, e.g. upgrading to WebSocket. |
| 102 | Processing | WebDAV: the request was received and is still being processed. |
| 103 | Early Hints | Preliminary headers (often Link preload hints) sent before the final response. |
2xx Success
| Code | Name | Meaning |
|---|---|---|
| 200 | OK | The request succeeded. |
| 201 | Created | The request succeeded and a new resource was created. |
| 202 | Accepted | The request was accepted for processing, but processing is not complete. |
| 203 | Non-Authoritative Information | Success, but the returned metadata came from a transforming proxy. |
| 204 | No Content | Success with no response body. |
| 205 | Reset Content | Success; the client should reset the document view (e.g. clear a form). |
| 206 | Partial Content | Only part of the resource is returned, in response to a Range header. |
| 207 | Multi-Status | WebDAV: the body contains status for multiple independent operations. |
| 208 | Already Reported | WebDAV: members of a binding were already listed earlier in the response. |
| 226 | IM Used | The server applied instance manipulations (delta encoding) to the response. |
3xx Redirection
| Code | Name | Meaning |
|---|---|---|
| 300 | Multiple Choices | The resource has several representations to choose from. |
| 301 | Moved Permanently | The resource has a new permanent URL; update links and bookmarks. |
| 302 | Found | The resource is temporarily at another URL. |
| 303 | See Other | Fetch the result at another URL with GET (common after a form POST). |
| 304 | Not Modified | The cached copy is still valid; no body is sent. |
| 305 | Use Proxy | Deprecated: the resource must be accessed through a proxy. |
| 307 | Temporary Redirect | Temporarily at another URL; repeat the request with the same method and body. |
| 308 | Permanent Redirect | Permanently at another URL; keep the same method and body. |
4xx Client error
| Code | Name | Meaning |
|---|---|---|
| 400 | Bad Request | The server cannot process the request because it is malformed. |
| 401 | Unauthorized | Authentication is required or the supplied credentials are invalid. |
| 402 | Payment Required | Reserved for future use; some APIs use it for billing or quota problems. |
| 403 | Forbidden | The server understood the request but refuses to authorize it. |
| 404 | Not Found | The server cannot find the requested resource. |
| 405 | Method Not Allowed | The HTTP method is not supported for this resource. |
| 406 | Not Acceptable | No representation matches the request's Accept headers. |
| 407 | Proxy Authentication Required | The client must authenticate with the proxy first. |
| 408 | Request Timeout | The server timed out waiting for the request. |
| 409 | Conflict | The request conflicts with the current state of the resource. |
| 410 | Gone | The resource was deliberately removed and will not return. |
| 411 | Length Required | The request must include a Content-Length header. |
| 412 | Precondition Failed | A precondition header such as If-Match evaluated to false. |
| 413 | Content Too Large | The request body is larger than the server allows (formerly Payload Too Large). |
| 414 | URI Too Long | The request URL is longer than the server will interpret. |
| 415 | Unsupported Media Type | The request body's Content-Type is not supported. |
| 416 | Range Not Satisfiable | The requested Range cannot be served for this resource. |
| 417 | Expectation Failed | The server cannot meet the Expect request header. |
| 418 | I'm a teapot | An April Fools' joke (RFC 2324): the server refuses to brew coffee because it is a teapot. |
| 421 | Misdirected Request | The request was sent to a server that cannot produce a response for it. |
| 422 | Unprocessable Content | The request is well-formed but has semantic errors (often validation failures). |
| 423 | Locked | WebDAV: the resource is locked. |
| 424 | Failed Dependency | WebDAV: the request failed because a previous request failed. |
| 425 | Too Early | The server will not process a request that might be replayed (TLS early data). |
| 426 | Upgrade Required | The client must switch to a different protocol, given in the Upgrade header. |
| 428 | Precondition Required | The server requires the request to be conditional (e.g. If-Match). |
| 429 | Too Many Requests | Rate limit exceeded; slow down and check the Retry-After header. |
| 431 | Request Header Fields Too Large | A header, or all headers together, are too large. |
| 451 | Unavailable For Legal Reasons | The resource is blocked for legal reasons, such as a court order or censorship. |
5xx Server error
| Code | Name | Meaning |
|---|---|---|
| 500 | Internal Server Error | A generic server-side error occurred. |
| 501 | Not Implemented | The server does not support the functionality required. |
| 502 | Bad Gateway | A gateway or proxy got an invalid response from the upstream server. |
| 503 | Service Unavailable | The server is overloaded or down for maintenance; try again later. |
| 504 | Gateway Timeout | A gateway or proxy did not get a timely response from upstream. |
| 505 | HTTP Version Not Supported | The HTTP version used in the request is not supported. |
| 506 | Variant Also Negotiates | Content negotiation configuration error on the server. |
| 507 | Insufficient Storage | WebDAV: the server cannot store the representation needed. |
| 508 | Loop Detected | WebDAV: the server detected an infinite loop while processing. |
| 510 | Not Extended | Further extensions to the request are required. |
| 511 | Network Authentication Required | The client must authenticate to gain network access (captive portal). |
Direct Answer
Use the HTTP Status Code Lookup when an API, browser, or server log shows a status code and you need to know what it means and what usually causes it.
The Five Status Code Classes
Every HTTP status code falls into one of five ranges, and the first digit alone tells you the general category of response before you even look up the specific code.
- 1xx (Informational): the request was received and processing continues.
- 2xx (Success): the request was received, understood, and accepted.
- 3xx (Redirection): further action is needed to complete the request, usually following a different URL.
- 4xx (Client Error): the request has a problem, such as bad syntax or missing authentication.
- 5xx (Server Error): the server failed to fulfill a request that appeared valid.
Codes Developers Frequently Mix Up
A handful of status codes are so commonly confused with each other that getting them right (both when returning them from your own API and when reading them from someone else's) is worth memorizing explicitly.
- 401 Unauthorized actually means unauthenticated (no or invalid credentials); 403 Forbidden means the credentials are fine but access isn't permitted.
- 301 and 308 are permanent redirects; 302 and 307 are temporary. The 307/308 pair explicitly preserves the original HTTP method and body, while 301/302 historically allow clients to switch to GET.
- 404 Not Found means the resource can't be located; 410 Gone means it existed before but has been intentionally and permanently removed.
- 502 Bad Gateway means an upstream server sent an invalid response, 503 Service Unavailable means the server is temporarily overloaded or down for maintenance, and 504 Gateway Timeout means an upstream server didn't respond in time.
How to Use Http Status Code Lookup
- Open the tool on this page.
- Enter or paste your input in the field provided.
- Review the result shown on the page, then copy or download it.
Reference
| Feature | Details |
|---|---|
| Purpose | Complete the utility task shown on this page. |
| Input | The value or content requested by the tool. |
| Result | The generated or processed output shown on the page. |
| Best for | Quick browser-based utility work. |
| Category | Developer Tools |
| Works on | Desktop, tablet, and mobile browsers |
Useful Related Tools
Frequently Asked Questions
What's the difference between 401 and 403?
401 Unauthorized actually means the request lacks valid authentication credentials, despite the confusing name; the client needs to log in or provide a valid token. 403 Forbidden means the server understood who the client is but that client simply doesn't have permission to access the resource.
What's the difference between a 301 and a 302 redirect?
301 is a permanent redirect, telling clients and search engines to update their records to the new URL going forward. 302 is a temporary redirect, indicating the resource is only at the new URL for now and future requests should still use the original URL.
What's the difference between 307/308 and 301/302?
307 and 308 explicitly guarantee the original HTTP method and request body are preserved on the redirect, which matters for non-GET requests like POST. 301 and 302 historically allowed (and in many client implementations still allow) the method to be changed to GET on redirect, which can silently break a POST request that expected to stay a POST.
What does 429 mean and how should a client respond?
429 Too Many Requests indicates the client has hit a rate limit. A well-behaved client should read the Retry-After header if present and back off before retrying, rather than immediately retrying and making the rate limiting worse.
What's the difference between 404 and 410?
404 Not Found means the server has no idea what resource is being requested at that URL, which could be temporary or a simple typo. 410 Gone is a deliberate statement that the resource used to exist at that URL but has been permanently and intentionally removed, which is a stronger signal for search engines to deindex it.
What's the difference between 502, 503, and 504?
502 Bad Gateway means a server acting as a proxy or gateway received an invalid response from an upstream server. 503 Service Unavailable means the server itself is temporarily unable to handle the request, often due to overload or maintenance. 504 Gateway Timeout means a proxy or gateway didn't get a response from the upstream server in time.
What does the 2xx class generally mean, and is 201 different from 200?
The 2xx range means the request succeeded. 200 OK is the general success response, while 201 Created specifically indicates that the request resulted in a new resource being created, commonly returned by a POST endpoint along with a Location header pointing to the new resource.
What is a 1xx informational response used for?
1xx codes indicate the request was received and the server is continuing to process it before a final response. 100 Continue, for example, tells a client that it's safe to proceed sending the rest of a large request body.