Keyword cannibalization is essentially when you have overused one or a bunch of similar keywords across one or multiple of your pages. Google acknowledges certain words when ranking your website, which is why the certain words should be used sparsely and efficiently across your platform.
Websites often use keywords to rank above other sites in a similar niche. However, by using too many similar keywords across multiple of your own web pages or blogs, you are competing more against yourself than anyone else. No two pages within your website should be exactly the same, so why use the exact same keywords. Target different keywords for different pages.
Another effect of having fairly identical target keywords across multiple pages is that the most relevant page could have the lower ranking. This makes the customer feel that they have landed on the wrong webpage (which they have), and creates more work for them to find the right one. User experience is also one of the most important factors of a website's CRO and sales success.
As smart as Google is, it too can sometimes get confused. By confusing Google with too many keywords, it raises its red flag and could mark your webpage as spammy, spoiling your chances of being a top rank of the search engine result page.
In terms of boosting website SEO, we use keywords to help Google determine what kind of products/service we offer as well as make potential customers feel like they’re in the right place. By using the right keywords effectively in your title tags, meta descriptions, and webpage content, Google will recognise your website as authentic, valuable and useful, therefore ranking your site higher in specific Google searches. To give any example, you might own a business that sells homeware online. Some keywords might include ‘homeware’, ‘furniture’, ‘kitchenware’, ‘lounge’, and ‘bedroom’ etc. The more optimised your site is with keywords and other SEO tools, the more likely your business will appear in the search engine of one of those search words.
If you sense that you may have overused some specific keywords across multiple pages of your website, simply do a Google search. “[your.site.domain] [keyword]”. Do multiple of your webpages show up? Does the page you would expect to rank first, rank first?
Then, search for the keyword by itself. Are the same pages showing up? And, how far down the search engine?
If the only webpage you expected to rank the highest in the search does, then keyword cannibalization is probably not an issue for you. If the webpage results are not what you had hoped for/expected, then it might be time for a keyword audit.
Revisit the web pages that are suffering from overused keywords. Are they both necessary? Are they of similar value? If not, it may be worth combining them. Google thrives off long, rich and valuable content, so give them something juicy to decipher with a wider range of keywords and it could positively impact your rank in the search results.
If you are unwilling to merge the content, or delete one of the pages, then you’ll need to consider which one is more important for a particular keyword. Utilise your internal linking by having the particular keyword as an anchor keyword on another webpage or blog, then have that anchor keyword link to the most relevant page. Google will take notice of this and will keep it in mind when determining your page’s value and rank in the search engine.
As well as having the resources to audit your website now, you can keep keyword cannibalization in mind when producing further content for your website. Use a few keywords that have been beneficial for your site in the past, as well as incorporating new target keywords relevant to the page topic/material.