Earlier this week SEMrush published its first voice search ranking factors study. It looked at multiple variables for more than 50,000 voice queries and their ranking impact on an Android smartphone, Google Home and Google Home Mini.
The factors examined included page speed, SERP features, links, use of HTTPS and readability. Here are the top-level findings and conclusions of the study:
- Nearly 80% of the answers across devices came from the top three organic results. For the Android smartphone, the percentage was slightly lower (72%)
- 70% of answers came from a “SERP feature” such as Featured Snippets or “people also ask”
- Page speed was critical across the board. Top ranking answers were much faster to load overall than other results.
- Linking matters (external and internal)
- Schema markup was not used by roughly 30% of answers, though it was by 70%
As the chart above indicates, SEMrush found that roughly 97% of Google Assistant answers across devices are from the top 10 organic results, while 77.2% are from the top three. Consistent with the top ranked organic results appearing in voice/Assistant results, most answers (69%) came from a “SERP feature,” with Featured Snippets being the most common. “People also ask” was another common source.
Results were different, however, on Android smartphones. There, Featured Snippet results showed up less often than on smart speakers. Presumably, the presence of the screen on the Android device is the reason why.
Schema markup has been a best practice for some time, with many SEOs arguing it’s critical for ranking in voice search. However, this study found that wasn’t always the case, with 30% of results not using schema. Google has said in the past that schema doesn’t impact Featured Snippets.
SEMrush observed that “the majority of answer sources did indeed use schema.” However, there wasn’t “a clear winner over which type of schema would most likely influence an answer being selected from the SERP.”
On the topic of links, SEMrush found more inconsistency across devices than with other variables: “keywords in backlink anchors and page titles [are] much more prevalent in Google Home and Mini results than Android.” SEMrush added:
Over 50% of answers with Google Home and Mini had backlinks with an anchor that appeared in the question, compared to less than 45% in the remainder of the top 10 results in the SERP. However, with Android, that figure is below the remaining average, signifying a lack of relevance in the case of smartphone devices.
There’s much more detail more for SEOs in the published post.