Which AI tools for B2B buyers shape the research phase?

During their research phase, B2B buyers mainly use general-purpose AI assistants: ChatGPT, Google AI (Overviews and AI Mode), Microsoft Copilot, Google Gemini and Perplexity. On top of that, internal, company-owned AI tools play a growing role. Which one a buyer picks depends above all on the software they already use at work. In this article you will see which AI tools for B2B buyers actually matter, why a buyer chooses one over the other, and what that means for your company’s visibility.

Which AI tools do B2B buyers use most?

The research phase is shifting from isolated queries to conversations with an AI assistant that immediately delivers a summarised answer. Research from analysts such as Gartner and Forrester confirms that a substantial and growing share of B2B buyers use generative AI to compare suppliers and products, often before they visit a single company website. These are the tools that keep coming back.

• ChatGPT. The best-known general assistant, often the starting point for a first exploration (“which suppliers of X are there in the Benelux?”). Read how to show up here in getting found in ChatGPT.
• Google AI (AI Overviews and AI Mode). The AI answer above the regular search results and Google’s separate conversational mode. Buyers often end up here without consciously picking an AI tool, simply by googling.
• Microsoft Copilot. The assistant built into Microsoft 365, Windows and Edge. For many business users this is the AI that is literally within reach while they work.
• Google Gemini. Google’s assistant, integrated into Google Workspace and the Google apps. Strongly present in teams that work with Google.
• Perplexity. An AI search engine that backs every answer with visible source citations. Popular with buyers who want to be able to verify the claims. See getting found in Perplexity.

In addition, larger organisations increasingly use internal AI tools that run on their own documents and approved sources. As an external supplier you have little direct influence there, other than through the public authority you build elsewhere.

What stands out is that these are all general assistants, not specialised procurement tools. The buyer asks their question in the same tool they also use to write an email or summarise a report. That lowers the barrier and explains why research is shifting so fast: no new software is needed, only a new habit. For you it means your visibility is not played out in a niche corner, but in the tools your buyer already keeps open all day.

Why does a buyer pick one tool and not the other?

The choice of an AI tool is rarely a conscious one; it follows from the buyer’s working environment. Someone who sits in Microsoft 365 all day naturally opens Copilot. A team on Google Workspace reaches for Gemini. Someone used to googling gets Google’s AI answer thrown in for free. And someone who wants a second opinion or a quick summary pastes their question into ChatGPT or Perplexity.

For you, the practical conclusion matters more than the exact split: you cannot know in advance which tool your buyer uses, so you have to be findable in all of them. The good news is that most of these assistants determine what counts as a trustworthy answer in comparable ways. Get your visibility right for one tool and you often gain ground in the others too. That is exactly why you do not need a separate strategy per tool, but a shared approach. That overarching approach is called GEO; you can read the basics in the GEO guide 2026.

In which stage of the buyer journey do they use AI?

AI weighs heaviest at the start of the buyer journey, in the research and shortlist stages, and less in the final decision. In the early stage the assistant does the broad legwork: it puts together a longlist of possible suppliers, summarises their offering and names the differences. That is exactly the moment where your brand is mentioned or not, and therefore lands on the shortlist or not.

As the purchase gets closer, the importance of human validation rises again. Research consistently shows that B2B buyers like to check the insights from AI with a salesperson or expert before they sign. So the AI stage does not decide who wins the deal, but it does decide who gets considered at all. If you are not mentioned in that first round, you never even reach the human conversations. How that research phase plays out for B2B specifically, you can read in GEO for B2B.

What does this mean for your company’s visibility?

To show up in these AI answers, your content has to be easy to extract and your brand has to appear on sources the AI treats as authoritative. An AI assistant does not invent its answer; it assembles it from texts it considers reliable enough. Two things therefore determine whether you get picked up.

The first is extractability. An assistant prefers to pull short, clear answers out of your text. Pages with clear headings, direct answers to concrete questions and factual, verifiable information are reused more often than vague marketing copy. So write the way a buyer asks, and give the answer straight away.

The second is authority through mentions. AI tools lean heavily on what third parties say about you: trade media, comparison sites, forums and industry sources. In this context, consistent, positive mentions in those places often weigh more heavily than classic backlinks. We worked that out in brand mentions over backlinks. Whether an AI links your brand to the right category and the right facts therefore depends on how the sources the assistant trusts talk about you.

At Customer Impact we steer this with a level-headed view: the goal is not to score on a vanity metric like “mentioned in ChatGPT”, but to be visible to buyers who genuinely deliver leads and revenue. That also means being honest about the limits: AI visibility is not a switch you flip, and nobody can guarantee a spot in an AI answer. What you can do is set up your content and your public authority so that the odds of being mentioned rise structurally. Which tools to use to measure your position, you will find in AI visibility tools.

The short summary

B2B buyers increasingly do their research via ChatGPT, Google AI, Microsoft Copilot, Gemini and Perplexity, plus internal company tools. Which one they choose follows from their working environment, so you have to be findable in all of them. That works with content that is easy to extract and with consistent brand mentions on sources the AI trusts. The AI stage does not decide who wins the deal, but it does decide who makes the shortlist; if you are not mentioned, you do not count. Want to know where your company stands right now in these AI tools and what you can concretely improve? Take a look at our approach to visibility in AI search engines or book your free intake.