Web Tools
HTTP Status Code Lookup
Find HTTP status meanings and next steps.
Matching status codes
1 result404 Not Found
4xx Client error
The server cannot find the requested resource.
Common causes
- Wrong URL
- Deleted page
- Missing route
- Unpublished resource
Practical next step
Check spelling, route registration, deployment output, and redirects from old URLs.
This lookup is a quick reference for common HTTP status codes. It does not make network requests or diagnose a live endpoint; server logs, response headers, route configuration, and application behavior can still change the real fix.
About This Tool
HTTP status codes are the compact signals browsers, crawlers, APIs, proxies, and servers use to describe what happened to a request. A code such as 404, 429, or 502 can point you toward a routing issue, rate limit, cache behavior, authentication problem, or upstream failure. This lookup gives quick plain-language context plus practical next steps without contacting the target website.
How To Use It
- Enter a status code such as 404, a phrase such as Not Found, or a troubleshooting word such as timeout or redirect.
- Filter by status class when you only want informational, success, redirect, client-error, or server-error codes.
- Read the meaning, common causes, and next step for each matching code.
- Use the copy button when you need to paste a code and phrase into a bug report, support note, or documentation.
Examples
Debug a missing page
Search 404 to confirm that Not Found usually means the URL, route, published resource, or redirect mapping should be checked.
Understand rate limiting
Search 429 to see that Too Many Requests often requires retry backoff, respecting Retry-After, or reducing aggressive repeated requests.
Separate proxy and app failures
Search 502 or 504 when a proxy or gateway is involved. These codes often point to upstream health, timeout, or network issues rather than a browser problem.
Useful Notes
Status classes at a glance
1xx codes are informational, 2xx codes indicate success, 3xx codes redirect or reuse cached responses, 4xx codes usually point to request or permission problems, and 5xx codes indicate the server or an upstream dependency failed to complete the request.
A code is a starting point
The same status code can have different root causes depending on framework routing, proxies, CDNs, authentication, cache settings, and application logic. Use the next-step guidance as a checklist, not a final diagnosis.
Useful for SEO and deployment checks
Redirect, not-found, gone, and server-error responses can affect crawlability and user experience. Confirm important production URLs return the intended status code after route, domain, hosting, or CDN changes.
Local reference
The lookup uses a built-in reference list and runs locally in the browser. It does not send the URL, call an endpoint, or inspect live response headers.
FAQ
Is 404 always bad?
No. A 404 is correct for a missing resource, but important pages, old URLs, and internal links should not unexpectedly return 404. Use redirects or restore content when the URL should still work.
What is the difference between 401 and 403?
401 means authentication is missing or not accepted. 403 means the server understood who or what is requesting but refuses access under its permission rules.
Should permanent redirects use 301 or 308?
Both are permanent redirects, but 308 preserves the original method and body. For simple page redirects 301 is common; for APIs or method-sensitive routes, 308 can be safer.
Does this tool test my URL?
No. It is a reference lookup only. Use browser developer tools, curl, logs, hosting dashboards, or monitoring when you need the actual live response from a URL.
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