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What is a 301 Redirect?

The HTTP 301 redirect status code indicates the requested resource has been permanently moved to a new location. It is also called 301 Moved Permanently.

If you have run a site for a while, you would have knowingly or unknowingly made some changes to your URLs. For example, you may have:

  • Migrated your site from httphttps
  • Changed your site’s permalink
  • Changed your domain name
  • Changed a page’s URL
  • Deleted a page
  • Moved a page
  • Merged multiple pages

Depending on what has changed, visitors and search engine crawlers may encounter a 404お探しのページが見つかりませんでした page or land on a different version of the page other than the one you want them to visit.

Sample of a 404 Not Found page

To prevent this, you can create 301 redirects. That way, visitors and search crawlers that visit the old URLs will be redirected to the new one. Search engines will also update their databases with the new URL.

The 301 Moved Permanently redirect belongs to the 3xx series of HTTP status codes.

  • 3 ステータス コードがリダイレクトであることを示します。
  • xx は a placeholder for two numbers that indicate the type of redirection.

How Does a 301 Redirect Work

The browser and server handle the 301 redirects without any input from your end. Here is a rundown of how it works:

You click a hyperlink, URL, or enter a URL into your browser’s address bar.

Sample of a URL entered into an address bar

Your browser sends an HTTP request to the server, requesting to access the resource located at the URL.

Sample of a browser sending an HTTP request to a server

The server responds with an HTTP 301 status code, indicating the resource is no longer available at that location and has been moved to a new location. The response code includes a 位置 header field containing the URI where the resource is now located.

Sample of a server responding with an HTTP 301 response code

Your browser makes a new request to the server, requesting to access the resource at the new location.

Sample of a browser sending the updated HTTP request to a server

The server sends the resource files to the browser.

Sample of a server sending some files to the browser

The browser then displays the files to you as a webpage.

Sample of a webpage

The above explanation is just a simple illustration. Browsers and servers communicate using Hypertext Transfer Protocol (HTTP), so the requests and responses are sent in HTTP format.

For example, a browser looking to access the webpage located at will send the below HTTP request to a server.

GET /index.html HTTP/1.1

The server will then reply with the HTTP 301 status code, indicating the page has been permanently moved. The response includes the current location of the resource.

HTTP/1.1 301 Moved Permanently 

The browser then sends another request to the server. It will request to access

GET /index.html HTTP/1.1 

The server then sends the files located to the browser, which then presents them to the visitor.

The 301 response code is typically invisible to the visitor. However, you can observe the redirection by monitoring changes to the URL you entered into the browser and the URL presented to you once the page is loaded.

For example, when we enter the unsecured into our address bar:

Example of the URL entered into the address bar

Our browser displays the secured https version of our site without any extra input from our end. This is a result of the 301 redirect that redirects visitors from the http to the https version of our site.

Example of the URL displayed after the redirection

Why the 301 Redirect is Important

The 301 redirect provides your site with several SEO and usability benefits. This helps to ensure that your site can rank and your visitors do not encounter usability and user experience issues when using your site.

1 301 Redirects Preserve Your Link Equity and Pagerank

Google assigns a value to all webpages based on the quality and quantity of pages that link to them. This value is called PageRank, and Google uses it to determine where your content will appear in search results. 

Pages also pass link equity when they link to your pages. Typically, the more high-quality links you get, the more link equity you receive and the higher your PageRank.

Moving your pages to a new URL will cause you to lose the link equity and PageRank associated with the previous page. However, with a 301 redirect, you can pass your link equity and PageRank to the new URL.

2 301 Redirects Help Google Determine Your Canonical URL

Most webpages can be accessed through multiple URLs. For example, typically lead to the homepage of the same site. 

Google identifies these pages as duplicates and selects one of them as canonical, that is, the main version of the page. 

Google uses several methods to determine which page is canonical. However, Google considers the 301 redirect a strong signal that you want it to consider the URL you are redirecting to as canonical.

3 301 Redirects Improve the User Experience for Your Visitors

When you move your pages without setting up a 301 redirect, your visitors will encounter 404 pages whenever they visit the old URLs. That will lead to a negative user experience and cause your visitors to click the back button or navigate to other content.

Setting up 301 redirects prevents this and ensures your visitors can access your content even after changing the URL. 

4 301 Redirects Help Preserve Your Backlinks

Many sites run SEO audits periodically, and one of the things they look out for is broken external links. These are links that originate from their site and point to nonexistent resources on other sites.

If you receive links from other sites and then delete the linked resource without setting up a 301 redirection, those links would lead to 404 pages. The linking site may discover these broken links during the SEO audit and replace them with links to other sites, including your competitors. 

To prevent that, you should set up 301 redirects that redirect your backlinks to the new URL. That way, the linking site is less likely to remove your URLs.

Google’s Recommendation on Using the 301 Redirect Code

Since you want to rank on Google, you should pay attention to what Google says about using 301 redirects on your site. Consider these recommendations as best practices. That is, the things you should do to get the most out of your 301 redirects.

1 Only Use 301 Redirects if You Will Not Return to the Old URL

Google recommends using 301 redirects when you are sure you will never return to the URL you are redirecting from. If you intend to return to the old URL in the future, consider using a temporary redirect like 302 Found instead.

2 Use Meta Refresh When You Cannot Set Up a 301 Redirect

Google recommends you set up your permanent redirections using the 301 redirect. When you cannot set a 301 redirect, say because you cannot access your server, Google recommends using the meta redirect instead.

Ensure that you set the meta redirect to zero seconds as Google treats meta redirects set to zero as permanent redirects. For example:

<meta http-equiv="refresh" content="0; url=">

In the above code:

  • http-equiv="refresh" tells the browser to redirect to the new page
  • content="0 tells the browser to redirect to the new page after zero seconds
  • url=" tells the browser to redirect to

3 Redirect Your Old Pages to the Corresponding New Page

When you change your site’s URL, Google recommends redirecting your old pages to the corresponding page on the new URL. 

For example, if you moved from, you should redirect the homepage from Similarly, you should redirect a page like to its new location at

4 Avoid Long Redirect Chains

Google recommends avoiding redirect chains wherever possible. A redirect chain occurs when multiple redirections exist between the initial and final URLs.

For example, URL A redirects to URL B, which redirects to URL C, which then redirects to URL D before finally redirecting to URL E.

Example of a redirect chain

Google only follows four or five redirects (hops) before it gives up and stops following the redirect. To ensure Google follows your 301 redirects, Google says you should keep your redirections preferably within one or two redirects, or at most, three redirects. 

5 Leave the Redirections for a Year or More

If you change your domain name, for example, you move from to, Google recommends leaving the redirections for a year or more before abandoning the old domain or repurposing it for other things. 

Google says this is necessary because 301 redirections happen at a page level. So, it needs to crawl each page on the old domain and follow it to its location on the new domain.

Google also needs to crawl the pages on the old domain a few times to be really sure that you have permanently moved. If Google encounters pages without 301 redirects on the old domain, it may assume you are still using the old domain. 

6 Update Your Internal Links and Sitemaps

When you set up a 301 redirect on your site, Google recommends you update your internal links, sitemaps, and other links to point to the new URL. 

Doing this assures Google that the content has actually moved to a new URL and makes it more likely that Google will select the new URL as the canonical URL for that resource. 


1. What Does a 301 Redirect Do?

A 301 redirect informs the browser that the requested resource is no longer available at the specified location and has been permanently moved to another location. The server then provides the browser with the current location of the requested resource. 

2. What Are 301 and 302 Redirects?

A 301 redirect indicates a resource has been permanently moved to a new location. In comparison, a 302 redirect indicates a resource has been temporarily moved to a new location. The 302 redirect indicates the resource will return to the previous URL at a later date, while the 301 redirect indicates that the resource will いいえ return to the previous URL. 

3. Is 301 Redirect Good for SEO?

The 301 redirect is good for SEO. It allows a webpage to retain its link equity, visitors, and PageRank. Google also uses the 301 redirect as a strong signal when deciding the page’s canonical URL.

4. How Do I Redirect Using the 301 Code?

You can set up 301 redirects on your server. Some Content Management Systems allow you to create 301 redirects from their settings. If you have WordPress, you can use third-party plugins to set up your redirections. You can refer to this guide on setting up 301 redirects in WordPress.

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