An HTTP status code is the server's compact summary of what happened when it received a request. Reading that code before changing configuration can save time because it tells you whether you are looking at success, a redirect, a client-side error, or a server-side failure.…

An HTTP status code is the server’s compact summary of what happened when it received a request. Reading that code before changing configuration can save time because it tells you whether you are looking at success, a redirect, a client-side error, or a server-side failure.

What WebLens checks

The WebLens HTTP Status tool sends a request to the supplied URL and reports the HTTP status, status message, host, and content type when available. Redirect handling is disabled for this check, so the response describes the requested endpoint before WebLens follows a redirect elsewhere.

Understanding the five status classes

2xx responses indicate success. A common example is 200 OK. A successful status means the HTTP exchange succeeded; it does not guarantee that the application content is correct.

3xx responses indicate redirection or another form of further action. 301 and 308 are commonly permanent redirects, while 302 and 307 are commonly temporary redirects.

4xx responses indicate that the request cannot be fulfilled as made. 400, 401, 403, and 404 are common examples. The server is reachable, but the request or resource has a problem.

5xx responses indicate a server-side failure. 500, 502, 503, and 504 often point toward application errors, upstream failures, unavailable services, or gateway timeouts.

How to troubleshoot with WebLens

  1. Enter the exact URL producing the problem.
  2. Run the WebLens HTTP Status Checker.
  3. If you receive a 3xx, inspect the redirect target and check the final destination separately.
  4. If you receive a 4xx or 5xx, use the code to narrow the next diagnostic step.
  5. For deeper context, inspect HTTP headers or Website Status.

Example: a 404 after a migration

A 404 tells you the server answered but could not find the requested resource at that URL. The next checks are usually the route, rewrite rules, application routing, deployment contents, and whether the URL changed during migration. A 404 is very different from a connection failure.

Example: a 502 from a reverse proxy

A 502 often means a gateway or proxy could not obtain a valid response from an upstream service. That shifts the investigation toward the proxy-to-origin connection, upstream health, service ports, and timeout configuration. The public endpoint is reachable enough to return the 502, so the failure is further inside the request path.

Redirects deserve a separate look

Because WebLens reports the immediate response for this tool, a 301 or 302 can be useful evidence that the endpoint is redirecting. Check response headers if you need the Location value. A redirect can be intentional, such as canonicalizing HTTP to HTTPS, or accidental, such as sending traffic between two hosts in a loop.

What a status code cannot prove

A 200 response does not prove that a page is usable, secure, or correct. A 503 does not identify which backend component failed. Status codes are evidence about the HTTP boundary; application logs, proxy logs, DNS, TLS, and service health provide the deeper explanation.

Use the exact URL

Testing the homepage can hide a route-specific problem. If an API endpoint, image, login page, or checkout URL fails, check that exact public URL. Small differences in path, query parameters, hostname, and scheme can produce different responses.

Need the code in front of you? Use the WebLens HTTP Status Checker with the exact URL returning the unexpected response.

Read the status together with the request path

A status code is meaningful only for the URL and request context that produced it. A 404 on the homepage is very different from a 404 on an optional image. A 401 on an API can be expected when authentication is missing, while the same code on a public landing page may indicate a configuration error.

For redirects, inspect the immediate response before assuming the final destination is healthy. A 301 or 308 can be a deliberate canonicalization step; a chain that moves between HTTP, HTTPS, and multiple hostnames may indicate conflicting rewrite rules.

Turn status codes into next actions

Use 2xx results to verify that the endpoint answered, then validate the content or application behavior. Use 3xx results to inspect redirect targets. Use 4xx results to investigate routing, permissions, authentication, and requested resources. Use 5xx results to investigate the server, gateway, upstream service, and deployment. The code narrows the search; logs and configuration identify the cause.