Keyword cannibalization is a concept some SEO experts tend to ignore. But duplicate content from content cannibalization and keyword cannibalization really can make a difference in how your pages appear in search rankings.
Use this guide to understand what content cannibalization and keyword cannibalization are and what they aren't, and how you can adjust your site for higher online performance.
Before we go any farther, we need to make one thing clear:
Content or keyword cannibalization aren't just having two pages about the same topic. They aren't even about having the same keywords on multiple pages.
Cannibalization is all about having content and keywords on your pages that look the same to Google.
Google doesn't just index keywords anymore. It also examines how your pages match the searcher's intent. Content that has been copied from other pages on your site (or, worse, from other sites) isn't problematic unless it uses the same keyword and matches the same intent as other pages. But how can you know how Google measures the intent of your pages?
What is keyword cannibalization?
You are probably familiar with the concept of keyword stuffing.
Keyword stuffing involves repeating a keyword over and over again, even adding it in a tiny font so it will be read by bots but humans can't see it. The result is spammy content that fails to match the reader's search intent.
Although keyword stuffing was a viable SEO strategy in the 1990s, it is heavily penalized now. Most content marketers take pains to keep target keywords under 2.0 percent of total words, unless they flow naturally in the writing of the piece.
Content cannibalization is a little different. One of the best definitions of content cannibalization comes from Google itself.
Several years ago, a Reddit AMA asked Google Webmaster Trends Analyst John Mueller:
How does Google view keyword cannibalization? Many marketers believe that posting multiple pages about the same topic confuses search engines and results in lower rankings.
John Mueller’s response was:
"We just rank the content we get. If a site has a bunch of pages with more or less the same content, they are going to compete with each other. It's a lot like a bunch of schoolkids all wanting to be first in line. Eventually, someone slips in front. Personally, I prefer a few strong pages over a lot of weaker content. Don't water down the value of your site."
Another way to cannibalize content and keywords is this:
If you can't decide which page on your site should be more highly ranked, Google can't either.
Here is an example of cannibalized content.
Suppose you run a website about shoes. Your content creators have cannibalized content so that your keyword for every page is "shoes." Your content does not take full advantage of page-specific long-tail keywords such as running shoes, women's shoes, tennis shoes, orthopedic shoes, and so on.
Keywords aren't the only factor that Google uses to rank your pages. You may still have pages that get good page rankings in the search engines.
But you will also have pages that don't rank at all, because Google sees them as duplicate content. Fewer customers will find those pages, and the total traffic to your site will be unevenly dependent on the performance of just a few pages.