404 Errors and SEO: How to Find and Fix Them Properly

A page that returns a 404 tells the browser and the search engine the same thing: this address does not exist. On its own, that is not a fault. The problem starts when links from your own site, your sitemap or somebody else's site still point at that address — and nobody told you.

Below I go through when 404 errors actually affect SEO, how to find them, and mainly how to decide what to do with each one. Because the common mistake is not the existence of a 404. It is redirecting everything to the homepage.

404, 410 and soft 404

404 Not Found is an HTTP status code. The server is saying there is nothing at this URL. Google eventually drops the page from the index and stops visiting it regularly.

410 Gone is a stronger signal: the content was removed permanently. Google treats it much like a 404, usually a bit faster.

Soft 404 is the worse case. The page visually says "product not found" or "this category is empty", but the server returns 200 OK. The search engine treats it as a valid page, indexes it and spends crawl budget on it. In Search Console it shows up under Indexing as Soft 404. This is the classic ecommerce illness: sold-out products left on their original URLs with empty content.

When 404s hurt and when they don't

Google repeats that 404 pages are not a penalty. That is true, but incomplete. There are three different situations.

A 404 nothing links to. An old URL nobody knows about, a product address rewritten three years ago. You do not need to do anything. Let it return 404 and move on.

A 404 with an internal link pointing at it. This is a real problem. A visitor clicks in the menu or in body text and lands on an error page. A crawler follows the link and hits a dead end. If you have dozens of these, the search engine burns visits on addresses that give it nothing, and gets to your new pages later.

A 404 that has external links or used to get traffic. The painful one. The page had rankings, backlinks, search traffic — and now it returns 404. All of that value is gone. This is exactly why checking 404s on a schedule is worth the time.

How to find 404 errors

You need three sources. Each one shows something the others don't.

Google Search Console

Under Indexing → Pages you will find the Not found (404) category. Google lists the addresses it visited and got an error for. For each one you can see how it discovered the URL — from a link, from the sitemap, or from an earlier indexing.

This list matters most, because it covers URLs Google actually knows about. Two caveats: it is not complete, and it updates with a delay.

A crawl of the site

Search Console will not tell you where on your site the broken link sits. Only a crawl does that. I go through the public pages and record the status code for every internal link. The output is a pair: the broken target URL plus the page the link is on. Without that second half you cannot fix anything, you can only guess.

Crawling also surfaces 404s Search Console will never report — links in the footer, or in old articles Google rarely visits.

Analytics and server logs

Analytics shows which 404 pages got traffic over recent months. Those are your priority cases: someone is reaching that address, so there is an external link to it or people have it bookmarked.

How to decide what to do with each 404

This is where most of the damage is done. Run every address you found through this logic.

Is there a new equivalent? The product moved to another URL, the article has a new address, the category got renamed. Set a 301 redirect to that specific new page. Not to the homepage.

No equivalent, but a close alternative exists? A sold-out product you will not restock, but you carry something similar. Redirect to the parent category or to that specific alternative. At least the visitor lands somewhere useful.

Content gone with no replacement? Leave the 404, or return 410. Do not invent a redirect. Google will read a redirect to unrelated content as a soft 404 anyway and will not pass the value.

Is it a typo in the link? Fix the link on the source page. A redirect here is not a solution, it is a patch.

Why not redirect everything to the homepage

Bulk-redirecting 404s to the homepage looks like a fast fix and is one of the worst things you can do. Google reads it as a soft 404, the original page's value is not carried over, and the visitor lands somewhere that has nothing to do with what they were looking for. Bounce rate goes up.

If you redirect, redirect to the closest existing page by content. If no such page exists, 404 is the correct answer.

An error page that actually helps

When a 404 is going to stay, make the page usable. The minimum:

• plain text explaining what happened, not just "Error 404"
• a search box
• links to main categories or your most visited pages
• the normal header menu and footer left in place

And one technical condition: the error page must return status code 404, not 200. Check it. Open any non-existent address on your site, open developer tools and look at the status code in the Network tab.

Ecommerce specifics

Online stores generate 404s faster than other sites. The usual sources:

Sold-out and discontinued products. If you will not restock, redirect to the category. If you will restock, keep the page alive with an out-of-stock notice and links to alternatives — otherwise you would have to bring the URL back from a 404 later.

Removed categories and filters. After a structure change, the old addresses stay behind in the sitemap and in internal links.

A sitemap full of stale URLs. If your sitemap contains 404 addresses, you are sending the crawler into nothing. A sitemap should contain only pages that return 200 and are meant to be indexed.

Redirect chains. When a product migrates for the third time you get A → B → C → D. Every hop costs time, and with longer chains Google stops following them.

What I do about it

During an audit I go through the public pages and record the status code for every internal link. The output is a list of broken links together with the address of the page they sit on — so you know where to fix, not just what is broken. The same pass finds sitemap URLs that do not return 200, and redirect chains.

Where a replacement can be determined, I propose a specific redirect target. You approve it or change it. You deploy the fixes through the WordPress plugin, the API, or a CSV export.

What I do not promise: that fixing 404s will lift your rankings. Repairing broken links is hygiene, not a growth lever. The effect tends to be indirect — the crawler reaches the content you want indexed sooner, and visitors stop hitting dead ends. I measure the real impact of every deployed fix 28 days before and after, so you can see whether anything changed or not.

How often to check

For an ordinary site with a few dozen pages, once a quarter is enough. For a store where the product range changes, once a month. After any migration, redesign or URL structure change, check immediately — that is when the largest batch of broken links appears at once.

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