How Similar are Google and Bing's AI Results for a site?

Now both Google and Bing offer some metrics to take a peek at how your website is performing in their AI offerings, I got to wondering how similar they are.

Google are rolling out their AI metrics through Google Search Console with their Generative AI performance report, which provides at this point only pages and impressions.

Bing got a bit of a jump on Google by offering their AI metrics through Bing Webmaster Tools with their AI performance insights report, which provides a bit more by bringing you queries and click information in addition to pages and impressions, or citations in the case of Bing.

Comparison of Metrics

Despite the more limited scope of Google's Generative AI performance report, we can still do some comparisons between the pages that they are showing.

I downloaded the data from both reports for a sample website, a medium sized e-commerce site, predominantly B2C, and compared the metrics side by side.

Pages and Impressions in Google vs Bing

I sorted the list of URLS (Pages) in both reports by the number of impressions/citations and then compared to see how many of the top pages in Google were also in the top pages in Bing.

So there's a bit of overlap, but not a huge amount, we're looking at a 10 - 20% overlap between the top pages in Google and Bing AI overviews.

With AI results, there's always some element of randomness and personalization, but it does suggest that the two search engines are prioritizing different content.

Is that different to traditional search?

I repeated the same exercise for the traditional search results, comparing the top pages in Google Search Console and Bing Webmaster Tools.

So, in traditional search, we see a slightly higher overlap between the top pages in Google and Bing, with 10 - 28% overlap compared to the 10 - 20% overlap in AI results, but it's not a huge difference. So it looks like the diversity in content being surfaced by the two search engines is similar in both traditional and AI search results.

Conclusions and caveats

There's perhaps some difference in citations in bing world and impressions in Google world, and this is just but one site, and other sites might show different results. But it does suggest that the two search engines are prioritizing different content in their AI offerings, but perhaps mostly because they are just more diverse in their ranking and selection of content than we perhaps assume.