SEO Split-Testing Lessons from SearchPilot Increasing Internal Linking

SEO Split-Testing Lessons from SearchPilot Increasing Internal Linking

This week, we asked our Twitter followers what they thought happened to the organic traffic of higher level category pages when we ran an internal linking test on a grocery website where we added links to some lower level category pages.

We shared that the lower level category pages saw an uplift in organic traffic. This was what our followers thought:

Twitter poll on internal linking test

Most believed there was no detectable impact on the higher level category pages….

In this test though – the higher level category pages also saw an uplift in organic traffic! Read below for the full case study:

The Case Study
Google’s creation of the PageRank algorithm to rank web pages was the idea that led to Google becoming the dominant search engine. PageRank is based on the assumption that important pages will get more links from other important websites. It works by considering the number of links to a page while giving more importance to links with a higher PageRank.

The concept of PageRank underlies the historical importance of links for SEO, but it doesn’t only apply to external links – PageRank can flow through internal links too. This effectively means that within your own website internal links can indicate the importance you place on different pages in addition to being just a way to navigate the site (if you want to read more on the subject, one of Distilled’s (now BrainLabs) senior consultants Tom Capper’s blog post on internal linking in 2018 and beyond is a good resource).

As such, internal linking tests are an important part of SEO split-testing. They tend to be more complex to build than pure on-page tests, as there are two groups of pages that will be impacted: the pages more links are placed on, and the pages being linked to.