Search common HTTP response codes with class and meaning.
Updated
| Code | Title | Group | Description |
|---|---|---|---|
| 100 | Continue | 1xx | Request headers received; continue request body. |
| 200 | OK | 2xx | Request succeeded. |
| 201 | Created | 2xx | Resource created successfully. |
| 204 | No Content | 2xx | Request succeeded with no response body. |
| 301 | Moved Permanently | 3xx | Resource permanently moved to new URL. |
| 302 | Found | 3xx | Temporary redirect. |
| 304 | Not Modified | 3xx | Cached resource still valid. |
| 400 | Bad Request | 4xx | Malformed request syntax. |
| 401 | Unauthorized | 4xx | Authentication required. |
| 403 | Forbidden | 4xx | Server understood request but refuses it. |
| 404 | Not Found | 4xx | Resource not found. |
| 405 | Method Not Allowed | 4xx | HTTP method not allowed for resource. |
| 409 | Conflict | 4xx | Request conflicts with current state. |
| 410 | Gone | 4xx | Resource permanently removed. |
| 422 | Unprocessable Content | 4xx | Semantically invalid request payload. |
| 429 | Too Many Requests | 4xx | Rate limit exceeded. |
| 500 | Internal Server Error | 5xx | Generic server-side failure. |
| 502 | Bad Gateway | 5xx | Invalid upstream response. |
| 503 | Service Unavailable | 5xx | Server temporarily unavailable. |
| 504 | Gateway Timeout | 5xx | Upstream response timeout. |
Quick start
Search status codes by number, title or error type.
Type code like 404 or keyword like timeout.
Inspect category and practical interpretation.
Use result while debugging API or backend responses.
In-depth guide
Every HTTP response carries a three-digit status code that summarises what happened. Knowing the families — and the handful of codes you meet daily — turns a vague "it broke" into a precise diagnosis. This reference lets you search any common code and read what it means in real API and web workflows.
200 OK, 201 Created, 204 No Content.301 permanent, 302 temporary, 304 Not Modified.400, 401, 403, 404, 429.500, 502, 503, 504.401 Unauthorized actually means unauthenticated — log in. 403 Forbidden means you are authenticated but not allowed. 502 Bad Gateway is an upstream server returning garbage to a proxy; 504 Gateway Timeout is the upstream not answering in time. 429 Too Many Requests means you hit a rate limit — back off and check the Retry-After header.
Type a code, title or keyword to filter the list. Pair the status with the response body and your server logs: the code tells you the category, the body and logs tell you the exact cause. A 500 with a stack trace in the body is far faster to fix than a 500 alone.
This is a static reference — nothing you type is sent anywhere. The search runs locally in your browser and no lookups leave the page.
Use this tool for quick browser-based work when you need an answer or output immediately. Use a dedicated application or automated workflow when you need bulk processing, approvals, or repeatable production rules.
It includes the most commonly used response codes across the 1xx through 5xx families — the ones you actually meet in API and web work.
Yes. Search matches the code number, the title, the family and the description text.
Yes. It is optimised for quick lookups while debugging APIs and backends.
401 Unauthorized actually means unauthenticated — you need to log in. 403 Forbidden means you are authenticated but not allowed to access the resource.
429 Too Many Requests means you hit a rate limit. Back off and check the Retry-After header for how long to wait before retrying.
502 Bad Gateway is an upstream server returning an invalid response to a proxy. 504 Gateway Timeout is the upstream server not responding in time.
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