What Triggers AI Overviews? 86 Factors and 146 Million SERPs Analyzed

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What triggers an AI Overview? What types of queries are most likely to generate an AIO, and which are relatively safe? Can we predict where AIOs will appear, and even target SERPs without them?

To answer these questions, we analyzed our database of 146 million SERPs and explored how often AI Overviews appeared for 86 different keyword traits, from YMYL to CPC to query length.

Across our data set, AI Overviews appear for 21% of keywords. But looking at specific keyword categories, some categories have as high as a 60% chance of triggering an AI Overview, and others as low as 1%.

  • AIOs appear on 21% of all keywords.
  • 99.9% of AIOs appear on Informational intent keywords
  • AIOs are 1.9x more common for non-branded keywords than branded keywords
  • AIOs appear on 46% of 7+ word queries
  • AIOs appear for 57.9% of all question queries
  • 44.1% of Medical YMYL queries trigger an AI Overview
  • Only 6% of news queries trigger an AI Overview
  • The categories with highest AIO share are Science (43.6%), Health (43.0%), Pets & Animals (36.8%), and People & Society (35.3%).
  • The categories with lowest AIO share are Shopping (3.2%), Real Estate (5.8%), Sports (14.8%), and News (15.1%).
  • Only 4% of NSFW queries trigger AIOs
  • Only 7.9% of local searches trigger an AI Overview

About this data

All data is from September 2025. Keyword categories are derived from our internal keyword categorization systems.

If you’re an Ahrefs user, you can access this data yourself. Just head to Keywords Explorer and use the SERP features filter to see all keywords that trigger an AI Overview, and filter by dozens of variables like intent, volume, and growth rate:

You can also analyze any brand, website, or product’s visibility in AI Overviews using Brand Radar.

Just enter your brand to analyze your mentions, citations, estimated impressions, and even share of voice across millions of AI Overviews:

AI Overviews appear on 20.5% of all SERPs (29,991,998 out of 146,122,391).

Put another way, most websites can expect to compete with a Google-branded, AI-generated blog post for 1 in every 5 of the keywords they target.

We can use this rate as a baseline to see whether different keyword characteristics—like intent, length, or CPC—make it more or less likely for AI Overviews to trigger.

Here’s a chart summarising our findings. Query types with a positive difference from the baseline (i.e. bars on the right of the mid-line) are more likely to trigger an AI Overview; those with a negative difference (bars on the left) are less likely to trigger an AI Overview.

99.9% of keywords that trigger AI Overviews are Informational in intent. 5.5% of AIO keywords are considered Commercial, 1.2% Transactional, and just 0.1% Navigational.

Sidenote.

Keywords can have multiple intent classifications, hence the total summing to greater than 100%.

Intent Count Percentage
Informational 29,959,542 99.9%
Navigational 26,413 0.1%
Commercial 1,657,560 5.5%
Transactional 366,400 1.2%

Relative to the baseline rate of 20.5%, we can see that AIOs are slightly more likely to appear for Informational keywords, but vastly less likely to appear for other intent types, especially Navigational. Just 0.09% of Navigational keywords trigger an AI Overview:

Intent AIO SERPs Total SERPs Percentage
Informational 29959542 140287290 21.4%
Navigational 26413 2909989 0.9%
Commercial 1657560 38117465 4.3%
Transactional 366400 17806400 2.1%

76.3% of keywords that trigger AIOs are considered non-branded (e.g. seo tools), with the remaining 23.7% categorised as branded searches ( e.g. Ahrefs).

Label Count Percentage
Branded 7,095,160 23.7%
Non-branded 22,896,838 76.3%

AIOs are 1.9x more likely to appear on non-branded queries, triggering on 13.1% of all branded queries and 24.9% of non-branded queries in our SERP database.

Label AIO SERPs Total SERPs Percentage
Branded 7095160 54150524 13.1%
Non-branded 22896838 91971867 24.9%

Compared to the baseline, AI Overviews rarely appear for 1-3 word queries, but often trigger for 5-7+ word queries.

It seems that the longer the search query, the greater the chance an AI Overview will appear. AIOs appear on just 9.5% of single-word queries, but that figure jumps to 46.4% of all queries with seven or more words.

Query length AIO SERPs All SERPs Percent
1 471691 4964588 9.50%
2 2537067 25594777 9.90%
3 5740261 40931537 14.00%
4 6315178 32365814 19.50%
5 5321458 19303206 27.60%
6 3935672 10753233 36.60%
7+ 5670671 12209236 46.40%

66.5% of keywords that trigger AIOs are categorized as questions.

Label Count Percentage
Question 10,045,913 33.5%
Not question 19,946,085 66.5%

In total, AIOs appear on 57.9% of all question queries, while non-question queries show a lower rate of AI Overviews compared with the baseline, at 15.5%.

Label AIO SERPs All SERPs Percent
Question 10045913 17361451 57.90%
Not question 19946085 128760940 15.50%

There seems to be little obvious correlation between keyword CPC buckets and AI Overview appearance, with most hovering within a couple of percentage points of our 20.5% baseline:

CPC (USD) AIO SERPs All SERPs Percent
0.00-0.10 2427764 8787818 27.6%
0.10-0.20 847079 4573228 18.5%
0.20-0.50 1740808 14057337 12.4%
0.50-1.50 2435272 13550276 18%
1.50-5.00 1511232 7709489 19.6%
5.00-20.00 302047 1576723 19.2%
20.00+ 20943 132852 15.8%

Almost a third (32.3%) of the keywords that trigger AI Overviews are categorised as YMYL (Your Money or Your Life) queries.

Given that YMYL queries are—according to Google themselves—deserving of extra care and attention, it seems surprising to see AI-generated answers so prevalent.

In fact, AI Overviews are more common for YMYL queries than normal queries. 34.3% of all YMYL queries trigger an AI Overview, far higher than our 20.5% baseline. Non-YMYL queries are less likely to trigger AIOs, at just 17.2%:

Label AIO SERPs All SERPs Percent
Not YMYL 20291372 117843464 17.2%
YMYL 9700626 28278927 34.3%

All YMYL categories—Medical, Financial, Safety, Legal, and Other—show an increased occurrence of AI Overviews.

This is especially true for Medical YMYL queries, with 44.1% of medical queries triggering an AI Overview—more than double the frequency at which AI overviews appear across all keywords.

Category AIO SERPs All SERPs Percent
Not YMYL 20291372 117843464 17.2%
Medical 5924866 13430263 44.1%
Financial 2027902 8859397 22.9%
Safety 1215129 3922977 31%
Legal 354573 1499855 23.6%
Other 178156 566435 31.5%

This has not gone unnoticed by SEOs in the healthcare industry:

If we categorise keywords by the industry they belong to, we can see that AI Overviews have hit some industries harder than others.

Compared to our baseline of 20.5%, the hardest hit categories are:

  1. Science (43.6%)
  2. Health (43.0%)
  3. Pets & Animals (36.8%)
  4. People & Society (35.3%)
  5. Internet & Telecom (30.3%)
  6. Reference (30.1%)
  7. Computers & Electronics (28.6%)

At the other end of the spectrum, AI Overviews seem unlikely to trigger for other industries, especially those related to commerce and news content:

  1. Shopping (3.2%)
  2. Real Estate (5.8%)
  3. Sports (14.8%)
  4. News (15.1%)
Category AIO SERPs All SERPs Percent
Adult 44106 3599311 1.2%
Arts_and_Entertainment 1882795 14009774 13.4%
Autos_and_Vehicles 1269893 6762380 18.8%
Beauty_and_Fitness 859603 4679157 18.4%
Books_and_Literature 317298 1526539 20.8%
Business_and_Industrial 936352 5757412 16.3%
Computers_and_Electronics 1675947 5862964 28.6%
Finance 1355373 5451993 24.9%
Food_and_Drink 1804833 9680182 18.6%
Games 736028 5362070 13.7%
Health 6638182 15436927 43%
Hobbies_and_Leisure 303138 2256793 13.4%
Home_and_Garden 1755813 9540446 18.4%
Internet_and_Telecom 377053 1244501 30.3%
Jobs_and_Education 1092337 6075319 18%
Law_and_Government 898760 3889739 23.1%
News 746414 4948735 15.1%
Online_Communities 218816 1071306 20.4%
People_and_Society 1665904 4722623 35.3%
Pets_and_Animals 1179593 3203717 36.8%