The best SEO agency for a full website audit is the one that audits for today’s search reality, not yesterday’s. Traditional SEO is no longer enough because AI Overviews are intercepting clicks, reshaping discovery, and changing what it means to be visible. In 2025, AI Overviews appear in 25.11% of Google searches, up from 13.14% in March 2025. At the same time, 73% of B2B websites suffered meaningful traffic decline from 2024 to 2025, with an average drop of 34%.
That shift is not theoretical. 58.5% of US Google searches now end without a click, compared with 59.7% in the EU, while 60% of all Google searches end without a click to any website. Some businesses have reported 20–40% traffic decreases since AI Overviews were introduced, and 94% of B2B buyers used a generative AI tool in their last purchase process. A modern SEO audit must now include AI visibility diagnostics, generative engine optimization (GEO), and zero-click search analysis.
A full SEO audit still covers the classic pillars: technical SEO, on-page optimization, structured data, content audit, and backlink analysis. But in 2025, those checks are incomplete unless they also measure AI visibility, citation readiness, and how well the brand can be surfaced in AI Overviews. The new standard is simple: ranking matters, but being cited matters too.
That matters most for long-tail search. 68% of keywords triggering AI Overviews have 100 or fewer monthly searches, and while 88–91% of AI Overview-triggering queries are informational, transactional queries grew from roughly 2% to 14% of triggers. The citation pattern is also revealing: 44.2% of LLM citations are drawn from the first 30% of content, 31.1% from the middle 30–70%, and 24.7% from the final 30%. Meanwhile, 76.1% of URLs cited in AI Overviews also rank in the top 10 of traditional search results, yet 59.6% of AI Overview citations come from URLs not ranking in the top 20 organic results, opening the door to smarter citation optimization.
| Audit Focus | Why It Matters in 2025 |
|---|---|
| Technical SEO | Supports indexability, mobile usability, and structured data |
| On-page optimization | Improves content clarity, hierarchy, and query relevance |
| Content audit | Identifies freshness, depth, and citation potential |
| AI visibility diagnostics | Measures AI Overviews, LLM citations, and zero-click impact |
In other words, a modern audit is not just about fixing broken pages. It is about making the site legible to search engines, answer engines, and AI systems that decide whether users click at all. The best SEO agency will treat these layers as one connected system.
AI Overviews are now a core part of search behavior. Search visibility is no longer limited to blue links, and a serious full website SEO audit has to account for that shift. The data shows a search environment dominated by AI summaries, answer engines, and zero-click behavior.
AI Overview presence grew from 6.49% in January 2025 to 24.61% in July 2025, then stabilized around 15–16% by late 2025, including 15.69% in November 2025. Approximately 20% of Google searches now display AI Overviews, and Google AI Overviews reach 2 billion monthly users globally. They are especially prominent on mobile, where 81% of AI overview queries occur, even though desktop accounts for 59% of AI Overviews and mobile for 39%. Mobile presence also skyrocketed 474.9% year-over-year.
Coverage varies sharply by country, which is why audit scope should be market-specific. Indonesia leads with 37.2% coverage, followed by the Philippines and Mexico at 29.1% each, India at 26.8%, Nigeria at 26.4%, Brazil at 25.2%, Peru at 24.9%, Japan at 24.8%, Ecuador at 24.77%, Colombia at 24.2%, Argentina at 22.9%, Chile at 21.6%, the United States at 20.5% in 13th place, Canada at 19.2%, and the United Kingdom at 19.1%.
The keyword and volume data behind those country figures is equally important. The United States reflects 43 million keywords analyzed and 8,815,000 AI Overviews; Indonesia 11M keywords and 4,096,000 AIOs; the Philippines 6.4M and 1,865,000; Mexico 12M and 3,496,000; India 30M and 8,026,000; Nigeria 1.6M and 423,000; Brazil 21M and 5,303,000; Peru 2.8M and 696,000; Japan 18M and 4,468,000; Ecuador 1.3M and 322,000; Colombia 6.5M and 1,573,000; Argentina 5.4M and 1,237,000; Chile 3.1M and 669,000. Additional figures include the UK with 44,818 SERPs, South Africa with 7,995, Nepal with 2,555, and Nigeria with 1,007.
AI Overviews also remain heavily informational, with 91.3% of queries in January 2025 falling into that category. That is why an audit has to inspect informational content performance, long-tail visibility, and the site’s ability to compete when the answer is summarized before the click.
The click problem is severe. Top-ranking pages lose 34.5% to 64.4% of organic clicks when AI Overviews appear. Ahrefs found a 34.5% lower average CTR for position #1, while Amsive reported an average 15.49% CTR decline across industries. For informational keywords, position #1 CTR fell from 5.6% in March 2024 to 3.1% in March 2025, a 44.6% decline. For AI Overview keywords specifically, position #1 CTR dropped from 7.3% to 2.6%, a 64.4% plunge.
That drop is not limited to the top position. Expected CTR without AI Overviews was 4.0%, but actual CTR with AI Overviews was only 2.6%, a 34.5% deficit against expectations. Desktop clicks fall by 50% when AI Overviews are present, mobile clicks fall by 30%, and clicks to all websites below an AI Overview drop by 34.5%. UK publishers report traffic declines of 40–60% when AI Overviews appear, while brands can see a 61% drop in organic CTR on target queries and a 58% lower average CTR for the top-ranking page.
The zero-click effect is just as dramatic. Zero-click rate jumps to 83% when AI Overviews appear, versus 34% without them. Overall, 58.5% of US searches and 59.7% of EU searches are zero-click, and 75% of mobile searches end without a click. Only 8% of users click a traditional result when an AI Overview is on the SERP, down from 15% without one, and just 1% click links inside AI Overviews. Another 26% of users end their session immediately after viewing an AI Overview.
Some industries face far greater exposure than others, which is why an audit should benchmark sector risk, not just site health. Health leads at 60.7% of searches with AI Overviews, followed by Home & Garden at 50.4%, Transportation at 31.4%, Animals & Pets at 30.9%, Food & Beverage at 24.9%, Professional Services at 23.8%, Retail at 23.2%, Finance at 22.9%, Legal at 21.5%, Insurance at 19.0%, Apparel & Fashion at 18.3%, Technology at 17.4%, Energy & Utilities at 17.4%, Education at 15.5%, Entertainment at 14.6%, Travel & Hospitality at 11.3%, Sports at 7.1%, Automotive at 5.8%, Real Estate at 5.2%, and Local Services at 2.2%.
The overlap effects are important too. When AI Overviews and featured snippets overlap, CTR loss reaches 37.04%. Non-branded keywords suffer a 19.98% CTR decline, and keywords not in the Top 3 see a 27.04% drop. Branded queries can see a CTR increase of 18.68% when AI Overviews trigger, but only 4.79% of branded keywords trigger them.
Search is being pulled into answer engines at scale. Google AI Mode reached 75 million users by December 2025, grew 4x since launch, surpassed 100 million monthly active users, and processes more than 1 billion queries per month. Its usage rose from 0.25% to over 1% of all searches in two months, and it carries a 93% zero-click rate.
ChatGPT reached 900 million weekly active users in February 2026, up from 400 million in February 2025, and logged 5.35 billion monthly website visits in February 2026. It also processed 2.5 billion queries per day in July 2025. Perplexity handled 780 million queries in May 2025 alone and reached 45 million monthly active users in H2 2025. Gemini grew 157% between April and September 2025 and reached 1.1 billion monthly visits after that growth.
The broader market confirms the shift. Total AI chatbot visits reached 55.2 billion in 2025, representing 81% year-over-year growth. US desktop and mobile AI platform visits grew 28.6% from January 2025 to January 2026, and ChatGPT held 79% of generative AI web traffic in September 2025. AI-powered search tools captured 12–15% of the global search market in 2025, up from 5–6% at the start of the year, while Gartner predicted traditional search volume would drop 25% by 2026 because of AI chatbots and virtual agents.
If you want to be cited, you need to understand what AI systems already prefer. In a Semrush study analyzing 230k prompts in October 2025, the top-cited domains in LLM responses were reddit.com 9.7%, linkedin.com 8.9%, wikipedia.org 7.6%, medium.com 4.8%, youtube.com 4.2%, google.com 4.1%, nih.gov 4.1%, forbes.com 3.4%, amazon.com 2.6%, and microsoft.com 2.4%.
Community platforms matter more than many brands expect. In early August, ChatGPT cited Reddit in close to 60% of prompt responses before collapsing to about 10% by mid-September, while Wikipedia was cited in roughly 55% of responses. 48% of AI Overview citations come from community platforms like Reddit and YouTube, Reddit accounted for 21% of Google AI Overview citations in June 2025, and 85% of brand mentions in AI answers originate from third-party pages rather than owned domains.
The citation blueprint is highly actionable. Web mentions outperform backlinks by a 3:1 ratio for AI Overview presence, pages with sequential headings and rich schema have 2.8x higher citation rates, and content with statistics cited every 150–200 words enjoys 30–40% higher AI visibility. Since 44.2% of LLM citations come from the first 30% of content, structure matters early. Those citations are drawn from an average of 13.3 sources in AI Overviews and 12.6 links in AI Mode. Only 10.7% of cited URLs overlap between AI Overviews and AI Mode, with 16% domain overlap, and pages not updated in 3+ months are 3x more likely to lose citations.
The business case is enormous. The AI Search Engine Market was valued at $18.84 billion in 2025 and is projected to reach $50 billion by 2033. The overall AI market is expected to hit $1,339 billion by 2030 with 36.6% annual growth, and AI is projected to add a 21% net increase to US GDP by 2030. The Generative Engine Optimization market stands at $848 million in 2025 and is projected to reach $33.7 billion by 2034, a 50.5% CAGR.
Investment is already accelerating. AI search advertising spend is projected at $1 billion in 2025 and $26 billion by 2029. 65% of businesses report better SEO results with AI, and 68% of marketers confirm higher ROI with AI-driven strategies. Still, only 23% currently invest in GEO measurement, even though 54% of US marketers plan to implement GEO within 3–6 months. Global generative AI adoption reached 16.3% by the end of 2025, up from 15.1% in H1 2025, with 24.7% adoption in the Global North, 14.1% in the Global South, and country adoption rates of 59% in India, 58% in the UAE, 53% in Singapore, and 50% in China.
User behavior shows why visibility alone is not enough. 7 out of 10 users read only the first lines of an AI Overview, while 88% click “show more” but often do not read the full answer; median scroll depth is just 30%. Still, 70% of users report some trust in AI-generated search results.
The upside is real. Visitors from AI search tools spend 68% more time on-site than those from traditional organic search, with a 45% longer time-on-site in holiday 2025 and a 33% lower bounce rate. AI referrals convert 31% better than non-AI traffic, and revenue per visit from AI referrals surged 254% year-over-year in the 2025 holiday season. AI-driven referral traffic to US retail sites jumped 693% YoY in holiday 2025 and 393% in Q1 2026.
Even so, AI search still accounts for only 1% of total web traffic, yet it converts 23x better than traditional search traffic. When a page gets cited inside an AI Overview, its CTR rises from 0.6% pre-citation to 1.08%. Brands cited in AI Overviews earn 35% more organic clicks and 91% more paid clicks than non-cited competitors, and LLM sessions from ChatGPT to websites grew from 17,000 in Jan–May 2024 to 107,000 in the same period of 2025.
Bottom line: if your audit does not measure AI visibility, zero-click loss, and citation performance, it is already incomplete.
A future-proof audit connects every recommendation to a measurable AI-era problem. The best SEO agency will not stop at technical checks. It will map technical risk, content depth, citation readiness, authority signals, and AI visibility diagnostics into one plan. That is how a full website audit becomes useful in the age of AI Overviews.
Technical & Infrastructure Audit: Confirm indexability, crawlability, and mobile-friendliness, because 81% of AI Overview queries are mobile while desktop still triggers 30% of US keywords. Validate structured data and rich schema implementation, since pages with rich schema have 2.8x higher citation rates. This is the foundation. If search engines cannot parse the site cleanly, AI systems are even less likely to cite it.
Content & GEO Audit: Examine the first 30% of each page because 44.2% of citations come from that zone. Add statistics every 150–200 words to support the documented 30–40% visibility lift. Use sequential headings and a clear hierarchy. Check freshness rigorously, because pages not updated in 3+ months are 3x more likely to lose citations. Also evaluate third-party brand mentions, since 85% of brand mentions in AI answers come from outside owned domains, and aim for the 3:1 mention-to-backlink ratio that aligns with AI visibility.
Authority & Off-Page Signals: Backlinks still matter because 76.1% of AI Overview-cited URLs rank in the top 10. Yet the fact that 59.6% of citations come from non-top-20 URLs proves smaller sites can win with the right GEO services. A smart audit will track citation overlap and stability, remembering that only 30% of brands stay visible from one AI answer to the next, while brands earning both mentions and citations have 40% higher reappearance.
AI Visibility Diagnostics: Check visibility in AI Overviews, AI Mode, and LLM responses. Measure CTR impact before and after AI exposure using real benchmarks such as Amsive’s 15.49% decline and Ahrefs’ 34.5% loss for position #1. The strongest audits use tools capable of analyzing 30M+ SERPs and 100M+ AI citations, matching the scale used in industry-leading research such as Brand Radar’s 108 million AI Overview queries and Conductor’s 21.9 million queries for 2026 benchmarks.
The choice comes down to one question: does the agency understand that AI Overviews grew from 6.49% to 25.11% and that this shift caused a 34.5% click reduction for top results? If not, the audit will miss the real problem. The best SEO agency for a full website audit is one that can measure AI-Overview tracking, build a GEO strategy, enforce content freshness protocols, and optimize technical schema in one cohesive process.
That capability matters now because the market is moving fast. Only 23% of marketers currently invest in GEO measurement, yet 54% plan to do so within 3–6 months. The agency you choose should already have those capabilities, not promise to build them later. A provider that can analyze AI citations, LLM responses, and zero-click impact is the one that can actually protect growth.
If your current provider is still delivering a traditional checklist, the gap is obvious. A modern SEO audit must assess technical health, content quality, backlinks, AI citations, and generative search visibility together. That is the standard Delante’s SEO Audit is built to meet.
Don’t let AI Overviews steal your traffic. Get a full website SEO audit that covers every aspect discussed in this breakdown—from technical health to AI visibility. The best SEO agency for a full website audit is the one that has already adapted to the data, and that is why Delante stands out. Book your SEO Audit now.
