Does adding more categories to your Google Business Profile dilute your ranking? We tested this common SEO belief with two real experiments.
We wanted to answer two important questions that many business owners ask:
To find the answers, we tracked two different businesses over several weeks.
To get to the bottom of the "Category Dilution" theory, we knew we couldn't just run a simulation. We needed real-world data from active businesses. We teamed up with two agencies who helped us run this experiment: Wiideman Consulting Group (who provided access to a Law Firm in California) and Jarvis Marketing (who provided access to a Medical Spa in Washington). Together, we tracked how their rankings would react to significant category changes.
For the Law Firm, we decided to stress-test the algorithm. We didn't just want to see if adding categories hurt rankings; we wanted to see what would happen if we took them away. We started with their standard 6 categories, then expanded to 9. Once we had that data, we did something drastic: we stripped the profile down to a single primary category. Finally, we restored the original 6 categories to see if the rankings would recover. This "stress test" was designed to show us exactly how sensitive Google's algorithm really is.
For the Medical Spa, we took a more conservative approach that mirrors what a typical business owner might do. We started with their baseline of 5 categories and simply added 4 more relevant categories. No deletions, no stress testing—just a straightforward expansion to answer a simple question: If I list more services, will I rank for more keywords without hurting my main ones?
How did we make sure this was a controlled experiment?
After weeks of daily tracking and thousands of data points, the results painted a clear picture for both businesses. Here is what the data showed.
For our California Law Firm, the data revealed exactly how sensitive Google's algorithm is to category changes. We tracked this business through four distinct phases to measure how adding, removing, and restoring categories directly impacts keyword rankings.
Here is the story the data tells:
This graph tracks how each individual category's ranking changed across the four phases of our experiment. Hover over any point to see the exact rank for that day, and click on any category in the legend to isolate it.
Rank Position: The average ranking across all 25 grid points for that category keyword. A rank of 1 means the business appeared first at every location; higher numbers mean lower visibility.
Ranking Position (1 is best) | Original New
Tip: Click any category to isolate it and see exactly how its ranking changed over time. Click again to show all. Lines dropping to "Not Ranking" mean the business stopped appearing for that keyword during that phase.
This graph shows the big picture: how the business performed across all categories combined. Notice the dramatic drop during the Contraction phase.
Avg Rank (Blue) · Appearances (Green) · Top 5 (Orange)
For the Medical Spa, we took a more conservative approach that mirrors what most business owners would actually do. Instead of stress-testing the algorithm, we simply wanted to see what happens when you expand your category list with relevant categories.
Here is the story the data tells:
This graph shows how each category performed before and after we added 4 new categories. Hover over data points to see exact rankings, and click any category to isolate it. Watch how the original categories (blue) stayed stable.
Rank Position: The average ranking across all 25 grid points for that category keyword. A rank of 1 means the business appeared first at every location; higher numbers mean lower visibility.
Ranking Position (1 is best) | Original Added
Tip: Click any category to isolate it. Notice how the original categories (blue) stayed stable even after adding new ones—proving category dilution is a myth for relevant additions.
This shows the combined performance across all categories. After adding 4 new categories in Phase 2, total appearances increased while average rank improved—more visibility without hurting existing rankings.
Avg Rank (Blue) · Appearances (Green) · Top 5 (Orange)
We started this experiment with two questions. Here's what the data told us:
Answer: No. Adding relevant categories did not hurt existing rankings.
To answer this question, we specifically analyzed only the original categories that were present before we made any changes. We tracked whether their rankings changed after adding new categories. Here is what we found: (hover over ranks to see the math)
Answer: Yes. More categories meant more visibility in search results.
To answer this question, we looked at all categories combined (original + new) and measured the average ranking, total appearances, and top 5 appearances. Here is what we found: (hover over numbers to see the math)
The Bottom Line: Category Dilution is a myth. Add all categories that genuinely describe your services — you'll get more visibility without hurting your existing rankings.
Does this mean I should add as many categories as possible?
No. Don't stuff categories. Only add categories that are relevant to services you actually provide. We do not suggest adding categories just for the sake of it.
What are the limitations of this study?
We tested 2 businesses over several weeks. This is real-world evidence, not a large-scale scientific study. There are other studies on this topic: Sterling Sky (2020), BrightLocal (2023).