A cached representation
Search ETag to compare 304 Not Modified, which supports reusing a cached representation, with 412 Precondition Failed, which can prevent an outdated write.
A curated reference of 36 widely useful registered codes. It omits many WebDAV, extension, obsolete, temporary, and unassigned entries. Check IANA for the full registry.
200 OK
The request succeeded.
Example: GET /products returns a JSON list.
36 matching codes
| Code | Name | Meaning |
|---|---|---|
| Continue | Interim permission to send the request body. | |
| Switching Protocols | The server accepts a requested protocol switch. | |
| Early Hints | Interim hints arrive before the final response. | |
| OK | The request succeeded. | |
| Created | The request created a resource. | |
| Accepted | Processing is accepted but unfinished. | |
| No Content | Success with no response content. | |
| Partial Content | The response carries a requested range. | |
| Multiple Choices | Several representations are available. | |
| Moved Permanently | The resource has a permanent new URI. | |
| Found | The resource temporarily uses another URI. | |
| See Other | Retrieve another resource to see the result. | |
| Not Modified | Reuse the cached representation after validation. | |
| Temporary Redirect | Temporary relocation preserves the request method. | |
| Permanent Redirect | Permanent relocation preserves the request method. | |
| Bad Request | The request cannot be processed as sent. | |
| Unauthorized | Valid authentication credentials are missing. | |
| Forbidden | The server refuses the requested action. | |
| Not Found | No current representation is disclosed or found. | |
| Method Not Allowed | This resource does not support that method. | |
| Request Timeout | The complete request did not arrive in time. | |
| Conflict | Current resource state conflicts with the request. | |
| Gone | The resource is intentionally unavailable, likely permanently. | |
| Precondition Failed | A supplied request condition evaluated false. | |
| Content Too Large | The request content exceeds server limits. | |
| Unsupported Media Type | The request content format is unsupported. | |
| Range Not Satisfiable | The requested range cannot be served. | |
| Unprocessable Content | The content is understood but its instructions fail. | |
| Upgrade Required | A different protocol is required. | |
| Too Many Requests | The client exceeded a request rate limit. | |
| Internal Server Error | An unexpected server failure blocked fulfillment. | |
| Not Implemented | Required request functionality is unsupported. | |
| Bad Gateway | An upstream server sent an invalid response. | |
| Service Unavailable | The server is temporarily unable to handle requests. | |
| Gateway Timeout | An upstream server failed to respond in time. | |
| Network Authentication Required | Network access needs authentication. |
Select a code for a concrete scenario. Status codes describe the HTTP response, not whether an application’s business operation ultimately succeeded; 202, for example, does not confirm completed processing.
Code numbers and standardized names are protocol facts. Explanations and examples are original, with no third-party commercial dataset bundled.
How to use the HTTP Status Code Reference
- 01
Search a code prefix such as 40, a name such as Gateway, or a scenario such as ETag.
- 02
Filter by response class and select a code to read its example.
- 03
Copy a selected explanation or download the filtered reference as CSV.
Examples
Choose a redirect deliberately
Search redirect to compare temporary and permanent relocations and whether request methods are preserved.
An accepted background job
202 can mean a report was queued. The application still needs a way to tell the client when processing actually completes.
Classes help narrow a diagnosis
The first digit groups the response: 1xx informational, 2xx success, 3xx redirection, 4xx client error, and 5xx server error. The more specific code, headers, request method, and application response together determine what a client should do.
Similar names can hide different causes
401 concerns missing or invalid authentication credentials and normally carries a challenge. 403 is a refusal that another login may not solve. At a gateway, 502 points to an invalid upstream response, while 504 points to an upstream timeout. Application logs and request context are still needed to diagnose the cause.
Scope and maintenance
The built-in dataset contains 36 selected codes with original short summaries and examples. It omits many extension, WebDAV, obsolete, temporary, and unassigned entries. Names and numbers follow the linked standards and registry reviewed on October 23, 2026. Use IANA and the defining RFC for complete protocol requirements or newer assignments.
What to know
- 36 selected codes; no claim of exhaustive coverage. The reference is bundled, not automatically synchronized with IANA.
Common questions
Why is a code missing?
The list is intentionally curated. A missing result does not prove a code is invalid or unregistered; check the complete IANA registry.
Does a 200 always mean the business task succeeded?
It indicates HTTP success for that request. An application can still place a domain-specific result in the response, and asynchronous work needs separate completion reporting.
Can this check my website’s status?
No. It does not contact URLs or send HTTP requests. It is an explanatory local reference.