What is an HTTP 404 error?
You've probably encountered "404 Not Found" or "404 Error Page" before. This is actually the most common HTTP status code. 404 means "the server cannot find the requested page." Simply put, the URL you clicked doesn't exist.
If it’s a little hard to understand, it’s like when you go to the supermarket to buy cheesecake, but the shelf is empty and the clerk doesn’t tell you where to look. This “can’t find” situation is called 404 Not Found.
3 major causes of 404 Not Found errors
The 404 Not Found error usually occurs when the server cannot find the resource the user requested.👉 Simply put, 404 means "the server is working, but couldn't find what you were looking for."There are three main common reasons:
Common causes of 404 errors include incorrect URL entry, deleted or moved pages, and server configuration errors.
1. URL error:
- The URL entered by the user contains typos or extra characters.
- The URL is capitalized incorrectly (some servers are case sensitive).
2. The page was deleted or moved:
- The webpage, image, or file has been deleted or moved, but the server is not configured to redirect it.
- The old link is still referenced, but the actual resource no longer exists.
3. Incorrect server settings:
- The routing rules on the server are incorrect, resulting in incorrect resource matching.
- .htaccess or Nginx/Apache settings are incorrect.
- Dynamic websites (such as PHP and Node.js) may experience errors when processing routes, resulting in a 404 error.
- The routing of front-end frameworks (such as React and Vue) does not have a fallback setting, and directly refreshing the page will result in a 404 error.
Do 404 errors affect SEO? What causes them?
404 error pages do not affect a website's SEO rankings, but if they are too numerous or handled improperly, they can reduce user experience and indirectly impact SEO results. But why do 404 errors indirectly impact SEO?
404 errors can lead to poor user experience, increased bounce rates, waste search engine resources, and interrupt the transfer of authority.
Poor user experience and increased bounce rate
Imagine a user clicks on a search result only to see “Page does not exist.” Most users will leave immediately. Google may then judge the website as unreliable, which will affect the ranking and increase the website’s bounce rate.
Waste of crawler resources
Every website has a certain “crawling budget.” If a crawler wastes time crawling through a bunch of 404 pages, important pages might not be indexed.
Internal and external link weight interruption
Internal links: A large number of links to 404 will weaken the SEO effect of the website structure.
External links: If the content cited by other websites returns 404, the website will lose its weight transfer and credibility.
Common HTTP status codes and error types
HTTP status codes In fact, they can be divided into five categories, and each number at the beginning has a different meaning. In fact, you don’t have to memorize all the codes, as long as you know the common error codes (such as 404 Not Found、500 Internal Server Error) and redirect codes (like 301、302), is sufficient to handle most situations encountered by websites.
300s Redirection
- 301 Permanent Redirect: Indicates that the page has been permanently moved to a new URL and the SEO weight will be transferred.
- 302 Temporary Redirect: Used for short-term adjustments or testing, the SEO weight of the old URL will not be transferred.
400s Client Error
- 401 Unauthorized: No access permission or authentication failed.
- 403 Forbidden: The server denies access due to lack of credentials.
- 404 Not Found (Page Not Found): The most common http error, indicating that the page does not exist.
500s Server Error
- 500 Internal Server Error: The server encountered an unknown error.
- 503 Service Unavailable: The server is temporarily unable to process the request, possibly due to excessive traffic.
- 504 Gateway Timeout: The server did not respond within the specified time.
You can check out this more detailed explanation: HTTP status code analysis: 3 steps to quickly troubleshoot errors and problems!
How do webmasters handle 404 errors?
The principle for website administrators to handle 404 is to fix what exists. There are three solutions to 404 not found:
1. 301 redirect the old URL
- 500 Internal Server Error: The server encountered an unknown error.
- 503 Service Unavailable: The server is temporarily unable to process the request, possibly due to excessive traffic.
- 504 Gateway Timeout: The server did not respond within the specified time.
2. Fix broken links on the site
Internal links to 404 errors can cause both users and Google crawlers to take a long detour. Remember to check your hyperlinks, menus, and even your sitemap to correct any broken links.
You can check out this more detailed explanation: Sitemap generation guide: Get it done in 5 minutes and have Google index your website in seconds!
3. Design a friendly 404 page
404 page errors are inevitable, so why not design a visually appealing 404 page? Include a link to your homepage, a search box, or even a recommendation for a popular article. This way, visitors won't immediately leave the page and will continue browsing your site.
4. Regular inspections
Cultivation and utilization Google Search Console Or use SEO crawler tools to regularly check error pages. Fix problems early and you don’t have to worry about bad links piling up.
SSL Certificate FAQ
Q1. How to solve HTTP 404 error?
Do a 301 redirect on the old URL
When an old page is moved or has external links, use 301 to direct people to the new page to preserve SEO weight and prevent visitors from getting lost.Fix broken links on the site
Check articles, menus, and sitemaps, and remove links pointing to 404 to make the process smoother for users and Google crawlers.Design a friendly 404 page
404 is inevitable. Design a page with a homepage, search box or popular articles to reduce the bounce rate.
Q2. What is the meaning of 404?
Webpage Error
The most basic usage is to mean "page not found." That's why "404" is used in internet jokes and memes to mean something disappeared, couldn't be found, or was abruptly interrupted.Can't find the status of the person
In the Chinese Internet context, "404" is often used to describe "disappearance, loss of contact, whereabouts unknown."Loss of understanding/unable to react
"404" is also used to describe "brain freeze" or "temporary disconnection".
Q3. What does 404 Not Found nginx mean?
404 Not Found nginx Just tell you: the server of the website (using Nginx There is a response (on the website), but the page you are looking for cannot be found. In other words, "the website is still there, but the page is gone."
Q4. What does 404 mean?
404 is a HTTP status codes, which means "Not Found". When the URL you enter does not correspond to any page or file on the server, the server will send back 404 Error, prompting "This page does not exist".
Q5. What does 502 stand for?
502 Bad Gateway This is a communication problem between servers. The web server you requested responded, but when it asked the backend for the data, it received an incorrect answer, so the web page would not display.
Insights into Digital Technology | Maintenance-free website company!
Anyone who runs a website must have encountered "404 Not Found", right?
In fact, 404 itself will not directly cause your ranking to drop, but if too many of them accumulate and are not handled properly, it will really affect the user experience and even waste Google crawler time, which will ultimately drag down your SEO performance.
Maintenance is actually not that difficult. If something is still there, fix it. If something needs to be deleted, leave it as a 404/410. If something needs to be moved, set a 301. This way, you can ensure SEO and user experience!
Insights into digital technology Designed for B2B, startups, manufacturing and education industries Create a professional website:
✅ Preset import SSL/HTTPS Architecture, avoid security warnings and trust crises
✅ SEO Architecture + Aesthetic Design, reduce the risk of errors such as 404 and enhance user experience
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👉 Don't let 404 errors drag down your brand image, make an appointment now Free consultation, and work with us to create a safe, stable and trustworthy website!
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