Search marketers go through great pains to acquire links. Links, in general, improve the rankings of a web site. As a result, an entire industry has been created around them. Much to Google’s chagrin, links are bought and sold. Product reviews are contrived – with links embedded, of course, and links are still cleverly exchanged in moderation to the same end. One great relevant link could spell the difference between page one and page two on a search engine results page. That could represent millions in your bottom line. Links therefore contain an equity in and of themselves – link equity. However, it is important to realize that not losing a link is effectively the same as acquiring one. In fact, old links may even be better.
So let’s explore the concept of link equity a bit. Then we’ll go through some measures you can take to preserve this equity when making changes to your web site. Such measures do not cost any money (except for a small amount of labor), do not break any search engine’s terms of service, and they certainly don’t require any time-consuming email solicitations. Preserving link equity, in fact, is much more fun and less stressful than all of this.
About Link Equity
Links give structure to The Internet, and provide both implicit and explicit information in the aggregate. They assign a value to web pages – a page with many links from relevant, reputable sources indicates to a search engine that it contains valuable information – and that, of course, influences its rankings in search engine results. Among all the factors that search engines take into consideration when ranking web sites, links have become paramount. Preserving them is certainly worthwhile. Link equity, then, is defined as the equity, or value, contained by a particular URL.
What do we mean by preserving links and link equity? Usually, once placed, links to web pages are present for a long time – in articles, reviews, and so on. Oftentimes, however, when web sites are redesigned, the URLs to the pages referenced by those links are invalidated. This effectively destroys the equity contained therein. Preserving it requires that steps be taken when undergoing redesigns.
So let’s explore 5 strategies to prevent link equity from being squandered – let’s preserve it instead:
1. Do not make frivolous URL changes
This may seem like common sense, but we have all seen many Fortune 500 companies do this multiple times in one year with design changes. Yes, design changes are sometimes necessary, but URL changes can often be avoided or measures can be taken to mitigate the damage from those changes. Typically that measure is a 301 redirect, which we’ll discuss in the following sections.
As a trivial example, let’s say your web site contains a product catalog in subdirectory “/catalog/” and you are prototyping a new one in “/catalogv2/.” The URL “/catalog/” is referenced on the home page. Ideally, when the new catalog is ready for production, the new one should be renamed to “/catalog/” and the old one archived. Simply changing the link that references it on your web site will not transfer any link equity that your catalog has acquired over time from external sources. A search engine will not read your mind – it will not know that “/catalogv2/ is the new rendition of “/catalog/.” Changes like these that can be avoided should be avoided.
2. When you must make URL changes, create a workflow for redirecting
Whenever a redesign occurs and old URLs are invalidated, require that a mapping be created from the old URLs to new URLs with similar content. Then use a 301-redirect to indicate that it replaces the old URL. If it is not possible for all URLs, do so for the ones that drive the most traffic in your analytics. Doing so can be as a simple as the following lines placed in .htaccess for Apache-based web servers:
RewriteRule ^foo\.php$ /bar.php [R=301,L]
This line redirects the file foo.php to bar.php.
Those few lines could spell an enormous difference in your bottom line. A similar procedure is used for Microsoft-based web servers. See http://www.webconfs.com/how-to-redirect-a-webpage.php for more information.
3. Strategically redirect old pages to related new pages where appropriate
Universally, product manufacturers release new models of products to replace outmoded editions. Widget Model B replaces Widget Model A. If model A was located at /Model-A.html, one can 301-redirect /Model-A to /Model-B.html.
This channels the legacy equity to related updated content. This practice is superior to returning a URL Not Found (404) error, both because it transfers equity contained by that URL instead of dispensing with it, as well as refers any old links and bookmarks to relevant updated content. In other words, it is not only advantageous with regard to rankings – it is potentially also helpful to users and search engines.
This may or may not be appropriate in every case, but it is usually desirable if your web site sells commodities. Google Webmaster Central conveniently lists all URLs that result in 404 errors; see http://www.google.com/webmasters/ for more details.
4. Ensure correct redirect codes are employed
It is a common mistake to use a 302 instead of a 301 redirect. A 302 redirect will not transfer link equity. Without looking at the headers sent to a web browser, it is impossible to know which were used. In PHP a 301 is sent like this:
header(“HTTP/1.1 301 Moved Permanently”);
Whereas a 302 like this:
header(“HTTP/1.1 302 Found”);
This difference in implementation is subtle, but the effects can be profound. If a change has been made permanently to a URL structure, a 301 redirect should be employed in order to preserve link equity. To check the headers returned by a particular page, you may use the tool located at http://www.seoegghead.com/tools/view-http-path.php.
5. Eliminate Duplicate Content
Very often in a dynamic web site, there exist multiple URLs to reach the same content. This is called duplicate content. Although an explicit penalty may not exist, users will often link to the various URLs indiscriminately. This has the unfortunate effect of dividing link equity. Therefore it is desirable to eliminate as much as possible for this reason as well.
As an example, suppose we have 2 pages with identical content:
When linking, one author references link 1, the other link 2. This effectively divides our link equity; and, furthermore, it is not clear whether a link to duplicated content is effective or useful.
Don’t Throw Away Equity
All of these strategies will help you to preserve the hard-earned URL equity that your web site has garnered over the years. It is especially important to consider the above when doing a comprehensive redesign of a web site. Understanding that URLs themselves contain a value is an important concept that many ignore, and ignoring it can result in a cataclysm for your business.