If you work in marketing, SEO, or content, you’ve felt the tremor. The rise of generative AI, led by tools like ChatGPT, has been seismic, prompting a flurry of urgent questions in boardrooms and strategy sessions alike. Is this the beginning of the end for Google Search? Do we need to pivot our entire SEO strategy to “AI SEO“? Is the ten-billion-dollar search industry on the verge of disruption?
A new, landmark study from Semrush, “ChatGPT Is Not Replacing Google, It’s Expanding Search“, offers a powerful, data-driven antidote to the hype. Their conclusion? The future isn’t a zero-sum game. ChatGPT isn’t replacing Google; it’s expanding the entire universe of how people seek information.
But what does this expansion actually look like? And how can marketers navigate this new, multi-modal landscape? Let’s dive into the data and explore the nuanced reality of how AI is reshaping, not replacing, digital discovery.
The Semrush Study: A Robust Look at Real User Behaviour
To move beyond speculation, Semrush analysed a staggering 260 billion rows of anonymised clickstream data from U.S. desktop users between January 2024 and June 2025. Their methodology was meticulous:
- Study Group: They identified users who used ChatGPT for the first time in Q1 2025 and tracked their Google Search activity for 90 days before and after that first interaction.
- Control Group: To account for natural variations in search behaviour, they also monitored a group of users who never used ChatGPT during the study period.
- Metric: The core metric was the number of daily Google Search sessions.
The results were clear and consistent across every cohort analysed. The data revealed no statistically significant decline in Google Search usage after people started using ChatGPT. In fact, there was even a slight increase in search activity. The control group, which never used AI tools, also showed stable patterns, confirming that the steady usage in the study group wasn’t just a broader trend.
This led Semrush to confirm the “Expansion Hypothesis” – the idea that AI adoption simply expands a user’s overall information-seeking toolkit, and reject the “Substitution Hypothesis,” which predicted that ChatGPT would directly replace Google queries.
The Bigger Picture: Corroborating Evidence from the Market
The Semrush findings aren’t an outlier. They align with a growing body of evidence that suggests generative AI and traditional search are settling into a complementary relationship.
The “Satisfaction Gap” in AI Responses
A study by BrightEdge (a leading SEO platform) found that while 81% of marketers believe generative AI will significantly impact SEO, user behaviour indicates a critical nuance. Their research suggests that users often turn to AI for broad overviews, brainstorming, and complex queries, but then “double-check” or seek more diverse perspectives and concrete details directly on the web via traditional search. This creates a “hand-off” effect where an AI interaction can actually trigger subsequent Google searches, precisely mirroring the expansion pattern Semrush observed.
Google’s Own Evolution with AI Overviews
Perhaps the most telling sign is Google’s own strategic integration of AI. Instead of building a separate product to compete with ChatGPT, Google is baking generative AI directly into its search engine results pages (SERPs) through AI Overviews. This indicates that the world’s largest search company sees AI not as an existential threat but as a feature that enhances its core product. Early data on AI Overviews shows they are initiating new search journeys. A user might get an AI-generated summary on “best hiking boots for wide feet,” which then prompts them to search Google for in-depth reviews on specific recommended brands like “Salomon Quest 4D GTX reviews” or “where to buy Hoka Speedgoat 5.” Again, search volume is expanded, not replaced.
Decoding the “Why”: How Users Are Dividing the Labour
The data tells us what is happening, but to build effective strategies, we need to understand why. User intent is the deciding factor. Consumers are intuitively learning which tool is better for which job.
When Users Might Prefer ChatGPT-style AI:
- Complex, Multi-faceted Questions: “Compare these Apple Laptops against these Microsoft ones.”
- Brainstorming and Ideation: “Give me 10 ideas for a 40th birthday party with a ‘roaring 20s’ theme.”
- Drafting and Summarisation: “Summarise the key takeaways from this PDF article into three bullet points.”
- Coding and Debugging: “Why is this Python function returning a null value?”
When Users Still Inevitably Turn to Google Search:
- Local Intent and “Near Me” Queries: “best coffee shop open now,” “emergency dentist downtown Seattle.”
- Commercial and Transactional Queries: “buy Nike Air Force 1 size 10,” “Booking.com hotels in Paris this weekend,” “Anker power bank Amazon voucher.”
- Real-Time Information: “live score Lakers vs Warriors,” “latest news on Hurricane [Name].”
- Seeking Diverse Perspectives: Reading a Reddit thread, checking a Trustpilot review, watching a YouTube unboxing video, or browsing a blog post for a personal experience. AI synthesises; Google provides a universe of individual voices.
This intent-based division of labour clarifies the expansion effect. A user might start in ChatGPT to understand a complex topic and then move to Google to find a specific product, local service, or real-world reviews from other people.
The Strategic Imperative: A Dual-Track SEO Strategy for Marketers
For marketing leaders and content creators, this reality is both a challenge and a massive opportunity. The mandate is clear: adopt a dual-track strategy that optimises for both traditional and AI-powered discovery.
Double Down on Foundational SEO (The Google Track):
Google isn’t going anywhere. It remains the primary conduit for commercial and local intent.
- Master Your E-E-A-T: Experience, Expertise, Authoritativeness, and Trustworthiness are more critical than ever. Google rewards content that demonstrates real-world experience and depth. Case studies, data-driven original research, and content written by verifiable experts will stand out.
- Optimise for the “Hand-Off”: Create content that serves as the perfect next step for a user coming from an AI tool. If an AI overview mentions “three best practices for X,” your article should be the deepest dive on “Best Practice #2” available on the web.
- Own Your Vertical: Dominate commercial and local search with robust technical SEO, a stellar user experience, and sharp, conversion-focused content.
Invest in AI SEO (The ChatGPT Track):
This is the new frontier. It’s about ensuring your brand and expertise are accurately represented within generative AI models.
- Optimise for Source Attribution: AI tools cite their sources. Your goal is to become one of those trusted sources. This means creating clear, authoritative, and well-structured content on your domain that AI models can confidently draw from.
- Think in Concepts, Not Just Keywords: AI understands user intent and semantic relationships. Build topical authority by creating comprehensive content clusters that cover a subject from every angle, rather than focusing on single-keyword pages.
- Structured Data is Non-Negotiable: Implement schema markup (like FAQ, How-To, and Article schema) to help AI models understand, parse, and contextualise your content more effectively.
Actionable Takeaways for Your Next Planning Session
- Conduct an AI Audience Audit: Use tools to understand if your target audience is adopting ChatGPT. Are they developers? Marketers? Students? Their adoption rate will dictate the urgency of your AI SEO efforts.
- Audit Your Content for “Answerability”: Review your top-performing content. How would an AI summarise it? Can you create more definitive, data-rich content that becomes the obvious source for AI to reference?
- Map the New Customer Journey: Sketch out how a user might interact with an AI tool when looking for a solution you provide. Where are the hand-off points to traditional search? Ensure you have touchpoints optimised for each stage.
- Monitor, Don’t Panic: Use analytics to track how traffic from brand and informational queries evolves. But remember the core lesson from Semrush: overall traffic is likely expanding into new channels, not just moving from one to the other.
The Final Word: A Bigger Pie, Not a Different Slice
The narrative of AI versus Search is compelling but ultimately flawed. The evidence shows we are not witnessing a battle for a fixed amount of user attention. Instead, we are seeing the creation of a new, larger ecosystem of information discovery.
ChatGPT and Google are becoming two different, powerful instruments in the user’s symphony of search. The winning brands will be those that learn to play both, understanding the unique music each one makes and how they harmonise to guide the customer to their door.
Ready to navigate the next era of search?
If you’re ready to evolve your search strategy, we can help you design a next-level discovery framework – one that unites AEO, GEO, and SEO for lasting impact. Contact us today!
Article author
Chiara Riva
Business Development Assistant
