A 404 error shows up the moment a visitor or search engine bot requests a page that no longer exists. On its own, a single 404 isn’t a disaster — Google treats them as a normal part of the web. But left unchecked across hundreds of URLs, 404 errors quietly chip away at user experience, waste crawl budget, and can erode the link equity built up by pages that once ranked well. If you’re serious about SEO performance, learning to find and fix 404 errors systematically should be a standing item on your technical SEO checklist. Here’s how to do it properly.

What is a 404 error, and does it hurt SEO?

A 404 “Not Found” status code tells a browser or crawler that the requested URL doesn’t exist on the server. In 2026, Google’s own guidance is clear that 404s don’t directly penalize rankings — they’re an expected part of how the web changes over time. The real damage is indirect: visitors who land on a dead page tend to bounce rather than dig further into your site, and if that broken URL had backlinks pointing to it, the authority those links passed on effectively goes to waste. At scale, a large number of 404s can also eat into your crawl budget, since search engine bots spend time hitting dead ends instead of discovering and re-indexing your genuinely valuable pages.

True 404s vs. soft 404s

It’s worth distinguishing a true 404 from a soft 404. A true 404 returns the correct HTTP status code along with a “page not found” message. A soft 404 happens when a broken or empty page returns a 200 “OK” status instead of a proper error code — common on JavaScript-heavy sites or headless CMS setups where the error message renders on the page, but the server doesn’t report it correctly. Soft 404s are worse for SEO because Googlebot keeps crawling and indexing pages it shouldn’t, which wastes crawl budget without ever giving you a clean signal that something is broken.

Top 5 ways to find 404 errors on your website

Before you can fix anything, you need a reliable way to surface every broken URL on your site. These five methods cover the most effective approaches, from free tools to a fully managed audit.

1. Conceptial Media’s technical SEO audit

For businesses that want 404 detection handled as part of a broader technical SEO health check rather than a one-off tool run, Conceptial Media offers full-site crawl audits that flag broken URLs, soft 404s, redirect chains and lost backlink equity in a single report. The advantage of going this route is that issues are prioritized by actual SEO impact — a 404 on a page with dozens of backlinks gets flagged well ahead of a dead URL nobody ever links to — and paired with a clear, prioritized fix plan rather than a raw export of broken links.

2. Google Search Console

Google Search Console is the free starting point for every site. Its Coverage (or Pages) report lists URLs Google has crawled and flagged as “Not Found,” making it easy to see exactly which broken pages search engines have already discovered. Reviewing this report monthly is a solid baseline habit even if you use other tools alongside it.

3. Screaming Frog SEO Spider

Screaming Frog crawls your entire site the way a search engine bot would, surfacing every 404, redirect chain, and broken internal link in one pass. It’s particularly useful for catching 404s Google Search Console hasn’t reported yet, since it checks every link it finds rather than only URLs Google has already crawled.

4. Ahrefs or Semrush broken-link reports

Both Ahrefs and Semrush include broken-link and backlink-audit features that cross-reference your site’s 404s against external sites linking to them. This is especially valuable for reclaiming link equity, since it shows you exactly which dead pages are still being linked to from other websites — the ones most worth fixing first.

5. Google Analytics

If your 404 page is tagged for tracking, Google Analytics can show you which broken URLs are actually being visited by real users, and where that traffic is coming from. This helps you prioritize fixes based on real-world impact rather than guesswork, especially for 404s generated by outdated internal links or old marketing campaigns still driving clicks.

How to fix 404 errors once you’ve found them

• Set up a 301 (permanent) redirect from the broken URL to the most relevant live page — never to the homepage by default, since that creates a confusing dead end for users.
• For content that’s genuinely gone and has no replacement, let it return a proper 404, or use a 410 “Gone” status if you want to signal removal is permanent and speed up de-indexing.
• Fix internal links pointing to broken URLs instead of relying only on redirects — a redirect chain adds latency and dilutes link equity with every extra hop.
• Reclaim backlinks by redirecting 404 pages that still have external links pointing to them, so that authority flows to a live, relevant page instead of disappearing.
• If you’re on a JavaScript framework or headless CMS, double-check that broken pages return an actual 404 status code rather than a 200 with error-looking content, which creates a soft 404.

Preventing future 404 errors

Fixing existing 404s is only half the job — the other half is preventing new ones from piling up. Build 301 redirects into your workflow any time a page is renamed, moved or deleted, and run a crawl audit before and after major site migrations or URL restructuring, when dozens of links can break at once. Monitoring should be ongoing rather than a one-time cleanup: set a recurring monthly check in Google Search Console, and treat any spike in 404s after a launch or campaign as a signal to investigate immediately rather than something to get to later.

Final thoughts

404 errors aren’t a ranking penalty waiting to happen, but they are a slow leak — in user experience, in crawl efficiency, and in the link equity your content has already earned. A regular audit process, whether that’s a monthly Google Search Console check, a Screaming Frog crawl, or a full technical SEO review from a partner like Conceptial Media, keeps that leak from turning into a real SEO problem. Treat 404 monitoring as routine site maintenance rather than a firefighting exercise, and it becomes one of the simplest, highest-leverage habits in your entire SEO program.