Boosting Internal Links Boosts Ranking: An A/B Test

Following our first strong internal linking results, we performed another A/B test to further evaluate the impact of increasing internal links specifically to pages ranking between positions 4 → 15 in search results.

Hypothesis

We expected that adding internal links to pages already ranking moderately well (positions 4 → 15) would enhance their visibility, increase their traffic, and improve their rankings due to stronger signals of relevance and authority.

Implementation

We split pages into three groups:

  • Boosted pages (pink): Received double the normal internal links.
  • Linked pages (blue): Received standard internal links.
  • Unlinked pages (green): Did not receive additional internal links through our internal linking tool, though they might still have received links from elsewhere on the site.

Results

The outcomes for the boosted pages were substantial: InternalLinking.io A/B test showing boosting inlinks boosts ranking and traffic

  • 43% increase in Googlebot crawling activity.
  • 19% more organic keywords ranking.
  • 27% increase in organic impressions.
  • 23% growth in organic traffic.

While linked and unlinked pages showed less significant changes, the boosted pages clearly demonstrated substantial performance improvements.

Understanding These Results

This test reinforced earlier findings, clearly demonstrating that internal linking significantly impacts search visibility, especially for pages already performing reasonably well. Boosting internal links provided additional signals to search engines about the relevance and value of these pages. These mid-ranking pages benefited notably from this extra authority, resulting in improved rankings, more organic impressions, and increased traffic.

The performance differences between boosted, linked, and unlinked pages illustrate the considerable benefits achievable by strategically increasing internal links.

Recommendations

Based on this test, we suggest:

  1. Regularly review and boost internal links to pages ranking in positions 4-15.
  2. Prioritize internal linking to pages with proven potential to improve quickly, maximizing their likelihood of moving into top-ranking positions and thus driving more significant traffic and conversions.