---
title: "404 error (Not Found)"
description: "The HTTP 404 error says no resource exists at a given URL. Learn where 404s come from, how they affect SEO and when a 301 redirect is the right answer."
url: "https://nodea.io/en/glossary/http-404-error"
lang: "en"
updated: "2026-07-13"
---

# 404 error (Not Found)

> The 404 Not Found error is an HTTP status code returned when the server works fine but no resource exists at the requested URL — the result of deleted pages, changed addresses or broken links.

**The 404 error** (Not Found) is an HTTP status code returned when the server is working correctly but no resource exists at the requested [URL](https://nodea.io/en/glossary/url). It is the most recognizable error on the web — every user has met it and every large site produces it — so the goal is not to eliminate 404s entirely but to manage them deliberately.

## How the 404 error works

Typical sources include pages deleted without a redirect, URL structures changed during a migration or redesign, typos in internal or external links, and misconfigured application routing. A separate phenomenon is the soft 404: a "page not found" message served with status 200, which confuses search engine crawlers into indexing an empty page instead of registering that the resource is gone. A correctly configured server returns a genuine 404 for missing addresses — or 410 when content has been removed permanently, signaling crawlers not to return.

## Practical applications

Good 404 management has three pillars. First, a helpful error page: navigation, a search box and links to key sections keep the visitor on the site instead of bouncing. Second, monitoring: the indexing report in Google Search Console and the server logs reveal which missing URLs receive traffic and where the links come from. Third, remediation: broken internal links get fixed at the source, while removed pages with valuable backlinks are pointed via a [301 redirect](https://nodea.io/en/glossary/301-redirect) to the closest relevant page. Keeping the [XML sitemap](https://nodea.io/en/glossary/xml-sitemap) current stops crawlers from revisiting long-deleted addresses. At scale, unmanaged 404s waste crawl budget and leak link equity — but the occasional one is simply part of a living website.

### Do 404 errors hurt SEO?

Isolated 404s are normal and do not lower the ranking of the whole site. Problems start at scale: internal links pointing nowhere waste crawl budget, and deleted pages with valuable backlinks lose the equity they pass unless 301 redirects are put in place.

## Related

- [301 redirect](https://nodea.io/en/glossary/301-redirect)
- [403 error (Forbidden)](https://nodea.io/en/glossary/http-403-error)
- [500 error (Internal Server Error)](https://nodea.io/en/glossary/http-500-error)
- [XML Sitemap](https://nodea.io/en/glossary/xml-sitemap)
- [URL](https://nodea.io/en/glossary/url)

---

Languages: [pl](https://nodea.pl/pl/slownik-pojec/bad-404.md)  
Site index: [llms.txt](https://nodea.io/en/llms.txt)