What HTTP status code message means?

Every Internet user and every webmaster have seen an HTTP code status instead of the web page at least once in a lifetime. Those codes are basically messages about the current status of the server and can tell a lot about the situation with the web page or with the server itself. Therefore, if a webmaster understands the meaning of the web request response code, he will be able to precisely diagnose the root of the issue and fix this on the server side without any problems.

It is highly vital for webmasters to also understand how web status code messages affect the users and how to deal with those issues as soon as possible. In particular, it is of high importance for webmasters to understand the meaning of each code displayed and what it means to client side (users) when they encounter such problems no matter where the root of the problem lies.

What is a response code

Web response codes, also known as HTTP codes, status codes and so on, are the basic form of replying to the requests sent by client (usually, by website user) to the server. Those are messages with three-digit numbers designated to convey info about the request result, or, basically, status reports. Those requests status code tell the client or the webmaster who is conducting diagnostics, about the current status of the resource and possible root of the occurring issues, if there are any.

Those service messages are divided into five separate groups representing a category of status code meanings and severity of the web resource state. This way, those codes allow the webmaster to determine the case and find a way to fix it. Therefore, those codes basically enable efficient resolving of various scenarios in the operation and development of web resources like sites, servers and applications.

If you work as a webmaster and know what one or the other web status code describes, you will be able to determine what happened on the server, how the internal structure or code was mishandled, or what situation occurred during the migration or update. It all will depend on the digits that were mentioned in the server error code report, and you will be able to easily resolve the situation.

For instance, the 404 code response or ‘Not Found’ error message shows that the requested object or URL is non-existent inside the server file system. This message usually shows up when something on the server is missing or its place inside the folder structure was changed. Such a situation often happens with a site that just finished a host-to-host migration.

On the other hand, a different code status that frequently shows up is 502 or ‘Bad Gateway’ that describes the situation when there’s something wrong with the network connection. Usually, this server response code tells the client (user) and the webmaster that the server and website are updating, migrating, under maintenance or are experiencing serious network load.

Response status code classes

The status code list starts from 100 and ends at 599, so it could be hard to tell them apart without a systematic approach. That's why all the codes are grouped into five categories, containing 100 codes each, and each category has its own dedicated guide below with the full breakdown, real examples and how to fix what it reports.

1xx status codes - informational responses

Codes in the 100-199 range are purely informational: the server is still working on the request and has not sent a final answer yet. They are usually logged in the background and rarely visible to end users, but they can point to delays or a misconfigured proxy along the way.

See what the 1xx informational codes mean and when you'll see them.

2xx status codes - successful request processing

Codes in the 200-299 range mean the request was processed successfully. Most of the time that's a plain 200 OK, but a few less common 2xx codes still deserve attention, since they can hint at oversized, missing or moved content even while technically succeeding.

See what the 2xx success codes cover and why some still deserve attention.

3xx status codes - server-side redirects

Codes in the 300-399 range mean the requested resource moved, temporarily or permanently, and the client is redirected elsewhere. That's normal after a URL change or a host-to-host migration, but a redirect that's missing or misconfigured turns into a broken link for users and search engines alike.

See how 3xx redirects work and when they signal a problem.

4xx status codes - user-side errors and mistakes

Codes in the 400-499 range point to a problem with the request itself, whether that's a bad URL, missing permissions or a client-side timeout. It's the group most users run into directly, and 400 and 404 are by far the most common.

See what the 4xx codes mean and how to fix them.

5xx status codes - server-side errors and issues

Codes in the 500-599 range mean the server itself failed to complete a valid request, from overload and misconfiguration to hardware or network faults. These are the codes worth alerting on immediately, since they usually mean the site is down for everyone, not just one visitor.

See what the 5xx codes mean and how to diagnose them.

Common status codes at a glance

Code	What it means	Class
200	OK - the request succeeded	2xx success
301	Moved Permanently - the resource has a new permanent URL	3xx redirect
302	Found - a temporary redirect to another URL	3xx redirect
304	Not Modified - the cached copy is still valid	3xx redirect
400	Bad Request - the request was malformed	4xx client error
401	Unauthorized - authentication is required	4xx client error
403	Forbidden - access to the resource is denied	4xx client error
404	Not Found - the resource does not exist at this URL	4xx client error
410	Gone - the resource was removed on purpose	4xx client error
429	Too Many Requests - the client is rate-limited	4xx client error
500	Internal Server Error - the server hit an unhandled fault	5xx server error
502	Bad Gateway - an upstream server sent an invalid response	5xx server error
503	Service Unavailable - the server is overloaded or down for maintenance	5xx server error
504	Gateway Timeout - an upstream server did not respond in time	5xx server error

How to check response codes on your site

There are three ways to see a request's status code. First, get it directly from the web resource by opening it in a browser or through an application - sometimes you get the code instead of the page itself. Second, if you have full access, search through the server logs, though this only shows what already happened and will not catch a new problem until you go looking for it.

Because the first two methods only show a single moment from a single vantage point, the third and most reliable way is constant monitoring with a tool built for it. HostTracker checks HTTP status codes from 300+ checkpoints across 158 cities, on a schedule or on demand with the free HTTP status code checker, and it can alert your team the moment a page starts returning something other than the expected 200.

FAQ

What is a status code

Basically, web response code or status code is the diagnostic report from the server. It tells the client (user’s device or webmaster’s diagnostic tool) about the status of the web resource, mainly - server. Speaking in technical terms, it’s a code that reports about the response to a client’s actions from the server. It works with the HTTP protocol and contains a specific number in the range from 100 to 599 that indicates the request processing state.

What is the most common HTTP status code

200 OK is by far the most common - it simply means the request succeeded. Among the codes that signal a problem, 404 Not Found is the one visitors run into most, usually because a link changed, a page was removed, or a redirect was never set up after a migration.

Do 4xx and 5xx errors affect SEO

Yes. Search engines that repeatedly hit a 4xx or 5xx response on a page they already indexed can drop it from the index and waste crawl budget on the rest of the site. Occasional, properly configured 3xx redirects are safe; what hurts rankings is an error that stays unnoticed and keeps repeating.

How can I check which status code my page returns

The fastest way is a purpose-built checker rather than a browser or a log file - HostTracker's free HTTP status code checker requests the URL and shows the exact code and headers in seconds, with no server access needed.

Can the same page return different codes for different visitors

Yes - depending on server rules, load, geography or bot protection, a page can return 200 for one visitor and 403, 429 or 503 for another. A single manual check from one location will miss that. HostTracker's distributed monitoring from multiple checkpoints is built precisely to catch region-specific and load-dependent problems that a single check cannot see.