What a 301 redirect is

A 301 redirect is the permanent way to tell the browser and Google that a URL has moved to another. Whoever requests the old one lands on the new one, and the signal from the old one can consolidate on the destination. People ask what it is, how it differs from a 302, and why opening one page opens another. This guide answers all three, without a shortcut that sends everything to the homepage.

What is happening when one URL opens another

You request an address. The server replies that the address no longer lives there and sends you to another. If the code is 301, the message is permanent. The browser shows the second page and, often, changes the address bar. That is why a user's question, "why does another page open," is the same answer as the technical one, seen from outside and from the server.

It is not a phone fault. It is not a virus. It is an instruction. It can be the right one, for example from http to https, or from the domain without www to the domain with www. It can be the wrong one, when every broken URL falls on the homepage.

What it keeps, and what it does not

Google treats a 301 as a move. The new URL can inherit the old one's signal if the content is equivalent. It is not instant and it is not a contract. If the new page talks about something else, there is no signal to consolidate: you have redirected one topic toward another.

A 301 does not fix a 404 on a page that should never have existed. And it does not replace the content. If you delete the guide and redirect to the homepage, the homepage does not become the guide. It stays a homepage with one extra visit and a query that no longer has an answer.

301, 302, and the mistake of leaving it half done

301 when the slug changes and will stay changed: an article that is renamed, a page merged with another, a new domain.
302 when the destination is truly temporary: a one-week landing page, a test. If the 302 is still there after three months, it was not temporary. Change it to 301 or remove it.
A chain. A redirects to B and B to C. The user arrives, more slowly. Google has to take two hops to understand the destination. Shorten it to one hop, from A to C.
A loop. A leads to B and B leads to A. The page does not load. You break the rule. You do not add a third one.

On a migration this is decided before the old site is turned off. The full procedure is in migrating without losing rankings. Here is the single piece, which is the one people search for by name.

When yes, and when no

Yes, from the old URL to the new one when the content still exists at another address. One to one. A product merged with another product, not with the homepage.
Yes, from the technical variants to the canonical: http to https, without www to with www, or the reverse if that is the one you chose. One version has to remain as the destination.
No, from everything that 404s to the homepage. It is the shortcut that takes the most rankings in a redesign, because Google stops seeing the old answers.
No, to "fix" a page you do not like. If the URL has to stop existing and there is no equivalent, a 404 or a 410 is more honest than a fake move.
No, in a chain every time someone renames a slug without looking at the redirects that already pointed at it.

Who implements it

The server or the platform puts it in place, not a paragraph in an article. On a classic host it can be a server rule. On a site built in a website tool, it is a redirects setting: old URL and new URL. The result is checked the same way: requesting the old one returns 301, and the destination is one URL.

Do not paste a rule copied from a forum if you do not know which URLs it touches. A broad line can also redirect the admin, the sitemap, or the page you wanted to keep. Test it on a handful of known URLs, the ones that had impressions, before you call the migration done.

How to check it landed correctly

Request the old URL with a tool that shows the status code, or from the browser's network panel. You should see 301 and, on the next line, 200 from the new URL. If you see 302, it is not the move you thought. If you see two 301s in a row, there is a chain. If the destination is the homepage for all of them, the map is wrong.

Search Console, in the following weeks, shows whether the old URLs become "page with redirect" and whether the new ones get indexed. That is the check. It is not that the browser opens the new page for you, because that also happens with a 302 or with a JavaScript jump that Google understands less well.

When the change is a whole template, the 301 is a piece of technical SEO, not a last-day chore. And the sitemap has to list the new URL, not the one that already redirects. That is explained in what a sitemap is.

301, 302, and 404 do not say the same thing

A permanent move is not an error and not a temporary change. The table is that split, with the decision that belongs on a business website.

Code	What you tell Google	When it is used
301	This URL has moved and is not coming back	A slug change, a domain change, or merging two pages
302	This URL is somewhere else for a while	A short test, or a destination that is truly temporary
404	This URL does not exist	A page you delete that has no equivalent
410	This URL was removed on purpose	Content you retired and do not want Google to keep requesting

Conclusion

A 301 is a move from one URL to one equivalent URL. It is not a shortcut from the whole site to the homepage. If you are going to change slugs or domain, the map is made before you publish, not when Search Console already shows the drop.

Frequently asked questions about 301 redirects

What is a 301 redirect?

It is a server response that sends whoever requests an old URL to a new URL, and says the change is permanent. The browser ends on the new one. Google can pass the old URL's signal to the new one. It is not a link inside the text, and it does not fix a page that never existed.

How is a 301 different from a 302?

A 301 says the move is final. A 302 says it is temporary. On a site migration, a 302 left in place for months tells Google about a change that never finishes consolidating. If the new slug is the one that will stay, the code is 301.

Why does opening one page open another?

Because there is a redirect. Sometimes it is correct: the old URL leads to the new one. Sometimes it is not: a plugin, a domain without www, or a bad rule sends people to the homepage or to another page. You check the status code. If it is 301 and the destination is not the equivalent, the rule is wrong even if the browser shows no error.

Does a 301 lose rankings?

A 301 to the equivalent page is how you avoid losing them when a URL changes. A 301 from every old URL to the homepage can lose them, because the homepage does not answer what each page used to answer. The code does not save a wrong destination.

Need a marketing team?

Let’s talk and grow your business