301 vs 302 redirects: what's the difference?

Redirects sound like a technical detail, but they're one of the highest-stakes settings on a website: pick the right kind and years of built-up Google rankings carry over to a new address; pick the wrong kind and those rankings can quietly stall or split. Here's what each one actually does, in plain language.

What is a redirect?

A redirect is an instruction your website gives to anyone who requests a page at its old address: "this page now lives over here — go there instead." Browsers follow it instantly, so a visitor clicking an old link or an outdated bookmark still lands on the right page. The number — 301, 302 — is the HTTP status code the server sends along with the instruction, and that code is what tells search engines how to interpret the move.

What does a 301 (permanent) redirect do?

A 301 says: this move is final. That one word changes how search engines behave:

• Rankings transfer. Google treats the new address as the successor of the old one and passes almost all of the old page's ranking authority to it. This is why a site can move to a new domain without starting from zero.
• The index updates. Over the following weeks, search results start showing the new address instead of the old one.
• Browsers cache it. Browsers remember a 301 and may jump straight to the new address next time without even asking your server. That's fast — but it also means a 301 is hard to take back once visitors' browsers have stored it.

Use a 301 for renamed pages, deleted pages that have a clear replacement, http:// to https://, www to non-www (or the reverse), and any site or domain migration.

What does a 302 (temporary) redirect do?

A 302 says: the page will be back — send people elsewhere for now. Search engines react accordingly:

• Rankings stay with the old address. Google keeps the original page in its index, because you've said it's coming back.
• Nothing transfers. The temporary destination doesn't inherit the original page's authority.
• Browsers don't cache it. Every visit checks with your server again, so you can remove the redirect at any time and the old page instantly works again.

Genuine 302 use cases are rare and short-lived: a product page redirecting to a "back in stock soon" notice, a page that's down for maintenance, or an A/B test.

Which one should you use?

If you're unsure, the answer is almost always 301. The situations that truly call for a 302 are the ones where you already know the page is coming back — and roughly when.

What happens if you use the wrong one?

A 302 where a 301 belongs is the classic, costly mistake. You migrate your site, set temporary redirects, and Google keeps waiting for the old pages to return — so the new pages don't inherit the old rankings for a long time. Google has become better at eventually treating long-lived 302s as permanent, but "eventually" can mean months of lost visibility you never needed to lose.

A 301 where a 302 belongs is the opposite trap: browsers and search engines commit to the move, and when you bring the original page back, cached browsers keep skipping past it. Undoing a widely-cached 301 is slow and messy — which is exactly why you shouldn't use one for anything temporary.

Redirects during a site migration

When a whole website moves — to a new platform, a new structure, or a new domain — 301 redirects are what carry your search rankings across. The rules of thumb:

1. Keep URLs identical where you can. A page that keeps its address needs no redirect at all, and nothing is safer than that. (This is why a faithful migration preserves your URL structure.)
2. Map every URL that changes to its closest equivalent — page to page, not everything to the homepage. Bulk-redirecting to the homepage wastes the old pages' authority.
3. Leave the redirects in place for at least a year. Old links live on in other websites, emails and bookmarks for years; redirects are cheap to keep.

Frequently asked questions