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To check whether a website is down, verify the exact URL, try it in a browser, then test from another device or network and inspect the HTTP response. A single failed load does not prove a site-wide outage: the problem may be a typo, a missing page, your browser, DNS resolver, network, or one server path.
Start with the exact address
Check the hostname and the full path, not just the site name. Look for misspellings, an extra or missing character, and whether the address should begin with www. Also check that you have not opened an outdated bookmark or a link with a path that no longer exists.
A site can be reachable while one requested page is missing. An HTTP 404 means the requested resource was not found; it does not, by itself, mean the whole website is unavailable. If the main page loads but a particular link returns 404, check that page’s URL and try navigating to it from the site.
Try a browser reload, then inspect the failed request
Reload the same URL once. If it still fails, note the exact browser message and whether the page is blank, partially loaded, or showing an error page. A browser’s wording can help distinguish a name-resolution problem from a connection timeout or an HTTP error returned by a server or intermediary.
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If you are troubleshooting your own site, open the browser’s Developer Tools and select the Network tab before reloading. Find the request for the page (and any failed resources), then record its status code, request URL, and response headers when available. The main document and its scripts, images, or API calls can fail separately, so identify which request actually failed rather than treating any missing image as a complete outage.
Compare another device or network
Open the same URL on another device, or switch between Wi-Fi and mobile data if available. This tests a different access path. If the site works on the second path, the first result points toward something local to the original browser, device, network, or DNS resolver; it does not prove the site is healthy for every visitor. If it fails on both, that still does not establish a universal outage, but it is stronger evidence to share with the site owner.
- Works in another browser on the same device: investigate browser settings, extensions, cached data, or a browser-specific issue.
- Works on mobile data but not Wi-Fi: investigate the local network or its DNS resolver.
- Fails on several independent paths: record the common URL and error details, then check the site owner’s official updates or report the problem.
Understand the HTTP response
An HTTP status code is evidence about a particular request, not a verdict on every page or user. The classes are 1xx informational, 2xx success, 3xx redirect, 4xx client error, and 5xx server error. A redirect (3xx) may be normal; follow the final destination and inspect its result.
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| What you see | What it usually indicates | What to do next |
|---|---|---|
| 404 | The requested page or resource was not found. | Check the hostname and path; try the site’s home page or navigation. |
| 5xx, such as 503 | A server-side or intermediary failure. A 503 is commonly used for temporary unavailability such as maintenance or overload. | Record the exact code, URL, and time; report it to the site owner. Site owners should check their host and, where relevant, proxy or origin. |
| No HTTP response; DNS lookup error | The hostname could not be resolved on that lookup path, so a normal HTTP response from the intended host was not reached. | Recheck spelling and compare another network or resolver; site owners should verify the expected DNS records. |
| Timeout or connection failure | The request did not complete along this path. It may be a local connection problem or a server, network, or intermediary issue. | Compare another access path and inspect the exact error before deciding where to investigate. |
A 5xx response is a useful clue, but it does not tell you whether the origin server, a proxy, or another part of the request path produced it. For owners, comparing the normal request with a direct-origin request can help isolate a CDN or proxy path, when that comparison is appropriate and the origin is safely accessible.
Use curl to inspect a request
curl sends an HTTP request outside the browser and can show response details such as headers. It is useful for separating a browser rendering problem from a request failure, but a command run from your computer tests only that computer’s network path.
curl -svo /dev/null http://www.example.com/Replace www.example.com with the hostname you are checking. To test a specific page, put its full URL in the command. The example uses HTTP; if the site is expected to use HTTPS, use its HTTPS address so you test the intended endpoint. Review the verbose output for the connection result, response status, and headers. Do not treat a successful response to one URL as proof that all pages or all visitors are unaffected.
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When DNS appears to be the problem
DNS is the step that finds the address associated with a hostname. A spelling mistake, missing or incorrect DNS record, or a problem with the resolver used by your device can all prevent that lookup. This happens before a normal HTTP response from the intended host, so you will not have an HTTP status code for a request that never reached it.
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example.com) or a subdomain such aswww.example.com. - Try the address from another network or resolver if you can. A different result suggests the issue may be specific to the first lookup path.
- If you own the site, confirm the expected records for both the apex and relevant subdomains, and check whether the records are present and correctly configured.
A DNS lookup failure on one device does not establish that the records are missing everywhere. Conversely, a successful lookup does not prove the web server is responding; DNS resolution and HTTP serving are separate steps.
Check status pages within their stated scope
Use a status page only when it covers a provider that is relevant to the failure. For example, Google’s Search Status Dashboard reports issues affecting systems that power Google Search; it is not a universal checker for unrelated websites. A clear dashboard means only that it does not report an issue within its stated scope. Continue testing the target site directly.
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Report an outage with details the owner can use
If a 5xx error persists, send the site owner the exact URL, response code or browser error, and the time it happened, including your timezone. Say whether the same page failed on another device or network. These details help the owner compare reports and investigate the relevant host or request path. If you are the site owner, preserve the failing response and timestamps and contact your hosting provider with those details; involve the CDN or proxy provider if evidence points to that layer.
Quick interpretation guide
- Typo or 404: verify the address and the specific resource before calling it an outage.
- DNS error: check the hostname and compare lookup paths; owners should inspect DNS records.
- 5xx: capture the status, URL, and timestamp and report them.
- Works elsewhere: focus on what differs in the failing browser, device, network, or resolver.
- Provider status incident: follow updates for that provider, while checking whether the target site itself is affected.
Or skip the browser setup
For a quick screenshot capture, ScreenshotNeo provides a website screenshot API; a screenshot can help you inspect what a page rendered, but it is not a universal uptime test. A capture result is most useful as one additional observation alongside the browser, network, DNS, and HTTP checks above. One GET request can return a PNG, JPEG, WebP, or PDF. See the ScreenshotNeo API documentation for request options.
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curl -G "https://api.screenshotneo.com/v1/shot" -d access_key=YOUR_API_KEY --data-urlencode url=https://example.com -o shot.webpScreenshotNeo accepts cookie or consent banners and removes more than 60 known consent platforms, newsletter popups, and chat widgets before capture; each of those steps can be turned off. Bot checks or CAPTCHAs, blank pages, timeouts, failed loads, and cache hits are not billed, and the response includes X-Page-Verdict and X-Billed headers. An MCP server offers take_screenshot, get_page_info, and capture_pdf for AI agents and MCP clients. The free plan includes 1,000 screenshots per month with no card; paid plans start at $5 for 3,000 shots. Those captures can show what the service received, but they cannot establish whether a site is down for everyone.
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Common problems and fixes
The homepage works but a link does not
Check the failing link’s complete path. A 404 is about that requested resource; try the site’s navigation or report the broken URL rather than assuming the whole site is down.
The browser says it cannot find the server
Check the spelling and whether you have the right hostname. If the address is correct, compare another network or resolver. For an owned site, verify its DNS records before troubleshooting page rendering.
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curl and the browser show different results
Confirm that both requests use the same full URL, including scheme and path. The browser may follow redirects or load additional resources; curl’s example is a separate request, not a full browser rendering. Compare the actual response and headers rather than only the displayed page.
The page works for someone else
Compare the access paths: device, browser, network, and resolver. A working result elsewhere narrows the investigation toward differences in the failing path, but does not identify the cause on its own.
A 503 or another 5xx keeps appearing
Save the exact code, URL, and timestamp with timezone. Send them to the owner; if you administer the site, use those details when contacting the host and compare proxy/CDN and origin behavior where appropriate.
Quick Recap
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