404 Not Found

The short version: As a visitor, look over the URL for typos first, then fall back to the website's homepage or search box. As the owner, 301-redirect any moved pages to their new URL, fix broken internal links, and crawl the site to surface every dead URL that needs attention.

Key takeaways

• A 404 means the server is up, read your request fine, and simply has nothing at that URL. The address is wrong, not the machine. That is why it sits in the 4xx client-error range.
• A genuine 404 returns the 404 status code. A soft 404 is the trap: it shows visitors a not-found message while telling machines 200 OK, which burns crawl budget and leaves dead URLs sitting in Google's index.
• When you delete something for good, reach for 410 Gone. Google handles 404 and 410 almost identically, but 410 says the removal is intentional and gets the URL dropped a touch faster.
• An ordinary 404 will not tank your rankings. The damage is indirect: broken internal links eat crawl budget, and any page with backlinks loses its link value unless you 301-redirect it somewhere relevant.
• Watch only the homepage and your monitor stays green while a deep product or article page quietly 404s. Check the URLs that actually pull traffic, and lean on content matching to catch the soft 404s hiding behind a 200.

Error type

HTTP 4xx client error

Whose side

Either: a bad link or the website

Fix difficulty

Easy

Common cause

Requested URL does not exist

What does 404 Not Found mean?

A 404 Not Found is how the server tells you it got your request, understood it, and has nothing to serve at that address. The server is healthy and answering, and that is what separates it from a 500: connection, DNS, and host are all fine, and only the specific resource at that URL is missing. Since the request is the problem rather than the server, the 404 lands in the 4xx family of client errors.

A 404 also tells you nothing about whether the page is gone forever. For content removed permanently, the server should answer 410 Gone, which is the clearer signal. Then there is the soft 404 to watch for: a page that shows a not found message to humans but still hands machines a 200 OK status. Search engines dislike soft 404s because they spend crawl budget on empty pages and can keep dead URLs indexed, so a missing page should return a real 404 or 410, never a 200.

404

HTTP status code

4xx

Client-side error class

410

Gone: the permanent sibling of 404

200

Status a soft 404 wrongly returns

How the 404 Not Found error appears

The wording changes depending on your browser, device, or server. Here is how this error commonly shows up:

example.com/old-page

404

Not Found

The requested URL was not found on this server.

• 404 Not Found
• HTTP Error 404
• 404 Page Not Found
• Error 404
• The requested URL was not found on this server
• 404 Not Found nginx

404 vs 410, 301 and 500

404 is one of several status codes that describe a missing or redirected page, and picking the right one tells browsers and search engines what really happened.

404 vs soft 404 vs 410 vs 301: what each one signals

These four responses describe a missing or moved page very differently, and the signal each sends decides how browsers, search engines, and link equity behave.

What causes 404 Not Found?

• A URL that is mistyped or out of date: an old bookmark, or a link printed somewhere that no longer matches the live address
• A page deleted or moved to a new URL with no redirect left behind to catch the old one
• A broken internal link pointing at a path that does not exist anymore
• A permalink or slug that changed after a CMS edit, restructure, or migration
• A file, image, or asset that went missing because it was renamed or never uploaded
• Case sensitivity on the server, where /Page and /page count as two different URLs
• Rewrite rules or .htaccess directives that are misconfigured and keep the server from resolving valid paths

How to find the cause fast

1. First, work out whether it is one URL or the whole site. If every page 404s, suspect a rewrite rule, a moved document root, or a broken router long before a single missing file.
2. Look hard at the URL: typos, a stray trailing slash, the wrong capitalization, an old slug. Then load the parent directory to see what is still there.
3. Read the server access and error logs. They confirm the request really returned 404 and show you which path was asked for and what referred the visitor.
4. Crawl the site with Google Search Console, Ahrefs, or Screaming Frog to pull every URL returning 404 along with the internal links still pointing at them.

Terminal

curl -sI https://example.com/old-pageHTTP/1.1 404 Not Found# a healthy page returns HTTP/1.1 200 OK

How 404 Not Found looks from the outside

An uptime monitor fetching a URL records the exact HTTP status it gets back, so a check aimed at a page that starts returning 404 tells you the moment it breaks. Here is the honest catch: point a monitor at your homepage alone and it will report everything healthy while a deep product or blog page throws 404s, so add checks for the URLs that actually earn traffic. The soft 404 is worse, since it returns 200 even though the page reads not found, and a plain status check waves it through. A keyword check closes that gap by loading the page and confirming the expected text is present, or flagging it when a not found message shows up instead. Pulsetic runs HTTP checks from 15+ locations every 30 seconds and can match on page content, so a broken or empty page surfaces fast.

To confirm the exact code a URL returns, or to re-test several at once after a fix, run them through the free bulk URL status checker.

How to fix 404 Not Found

If you are a visitor

1. Look over the address for typos, extra spaces, or wrong capitalization, then load it again.
2. Strip everything after the domain and climb back one directory at a time until a page loads.
3. Search for the content by name using the website's own search box.
4. Search the web for the page title or topic plus the website name, since the URL may simply have changed.
5. The page might be gone for good. Look for an equivalent elsewhere on the website.
6. If a link on the same website sent you there, give it one reload before giving up, since the page may just be slow.

If you run the website

1. 301-redirect any moved page to its new URL so visitors and link value both follow.
2. Track down broken internal links and repoint them at live pages instead of dead paths.
3. Restore or rebuild a page that was deleted by mistake but still pulls traffic or backlinks.
4. Build a helpful custom 404 page with your navigation, a search box, and links to popular content.
5. Review your rewrite rules, permalink settings, and .htaccess so valid URLs resolve correctly.
6. Crawl the website on a schedule to catch new 404s before users and search engines do.
7. Reach for 410 Gone on content you have deliberately and permanently removed with no replacement.
8. Resist blanket-redirecting every 404 to the homepage. Search engines can read that as a soft 404, and it frustrates visitors who wanted a specific page.

Still not fixed? Next steps

• When every URL 404s, not just one, stop looking for a missing file. Something upstream is routing valid paths to the 404 handler: a broken rewrite rule, a document root that moved, a wrong try_files in nginx, or a router that has crashed.
• In Search Console, open Pages to get the list of 404s Google actually sees. Then run that list against a crawler such as Screaming Frog or Ahrefs to spot which dead URLs still carry internal links or backlinks worth redirecting.
• With a single-page app, make sure the server returns a real 404 for routes it does not recognize. Client-side routing loves to render a not-found view while the server keeps answering 200, and that is a soft 404 search engines will flag.
• A page that 404s only some of the time points at a few suspects: a CDN edge that cached the 404, a case mismatch (/Page vs /page), or a deploy that dropped the file. Purge the cache or restore the file accordingly.

Code & configuration

Copy-paste starting points. Replace example.com and the paths with your own, and test changes on staging before production.

301-redirect a moved page (nginx)

# In the server block, send the old path to its new home
location = /old-page/ {
    return 301 /new-page/;
}

301-redirect and a custom 404 page (Apache .htaccess)

# Permanent redirect for a moved URL
Redirect 301 /old-page/ https://example.com/new-page/

# Serve your own 404 design for everything else
ErrorDocument 404 /404.html

Set a custom 404 page (nginx)

error_page 404 /404.html;
location = /404.html {
    root /usr/share/nginx/html;
    internal;
}

How to prevent 404 Not Found

A 404 on a key page bleeds traffic and conversions quietly, and if it stays broken, search engines may drop the URL altogether. Pulsetic watches the specific pages that matter from multiple locations every 30 seconds, and its keyword checks confirm the right content actually loads, so a page that starts returning 404, or silently shows a not-found message, reaches you by email, SMS, Slack, and more before a customer or Googlebot stumbles on it. It watches from the outside, not your server's internals.

Learn how Pulsetic's uptime monitoring detects this from the outside, across 15+ locations.