The AI search landscape in 2026 is defined by four major platforms: ChatGPT (OpenAI), Perplexity, Google AI Overviews, and Claude (Anthropic). Each platform uses a different approach to generating answers, citing sources, and serving users.

For UK businesses building an AI visibility strategy, understanding these differences is not optional. The content that earns citations on Perplexity may not earn citations on Google AI Overviews. The entity signals that matter for ChatGPT may carry less weight on Claude. An effective GEO strategy accounts for all four.

This page provides an overview of each platform, explains how it works, and links to MarGen’s detailed platform-specific guides.

ChatGPT (OpenAI)

What It Is

ChatGPT is OpenAI’s conversational AI platform, used by an estimated 200 million people globally as of early 2026. In the UK, ChatGPT is the most widely used AI tool among professionals in financial services, legal, and technology sectors.

How It Generates Answers

ChatGPT generates answers primarily from its training data — a vast corpus of text from the internet, books, and other sources with a knowledge cutoff that is periodically updated. With the introduction of browsing capabilities, ChatGPT can also access real-time web content when answering questions.

How It Cites Sources

ChatGPT’s citation behaviour varies by mode. In standard conversational mode, it rarely provides explicit source links. In browsing mode, it includes inline citations with links to source pages. The browsing mode is where GEO strategy has the most direct impact.

What Earns Citations

UK Usage

ChatGPT is the default AI tool for most UK knowledge workers. A 2026 survey by the Chartered Management Institute found that 58% of UK managers use ChatGPT at least weekly for research and decision support.

Perplexity

What It Is

Perplexity is an AI-powered answer engine that positions itself as a direct alternative to Google. Unlike ChatGPT, which is primarily a conversational tool, Perplexity is built specifically for information retrieval with source attribution.

How It Generates Answers

Perplexity searches the web in real time for every query, then synthesises an answer from the sources it finds. It uses multiple AI models (including its own and third-party models) to generate responses.

How It Cites Sources

Perplexity is the most citation-transparent platform in AI search. Every answer includes numbered inline citations with direct links to source pages. Users can see exactly which sources informed each part of the answer.

What Earns Citations

UK Usage

Perplexity’s UK user base is growing rapidly, particularly among early adopters in technology, finance, and professional services. While smaller than ChatGPT’s audience, Perplexity users tend to be high-value decision makers — the exact audience most B2B firms want to reach.

Google AI Overviews

What It Is

Google AI Overviews (formerly Search Generative Experience / SGE) is Google’s integration of AI-generated answers directly into search results. When triggered, an AI Overview appears above organic results, providing a synthesised answer to the user’s query.

How It Generates Answers

Google AI Overviews draw from Google’s own search index. The AI model synthesises information from pages that Google has already crawled and indexed, weighted by the same trust and authority signals that inform organic rankings — plus additional factors specific to AI generation.

How It Cites Sources

AI Overviews include links to source pages, typically displayed as cards beneath the generated answer. The number of cited sources varies, but typically ranges from three to eight. Being cited in an AI Overview drives measurable referral traffic.

What Earns Citations

UK Usage

AI Overviews appear on approximately 40% of UK commercial search queries in 2026. Because they are embedded in Google search itself, exposure is massive — every Google user encounters them, whether they sought AI assistance or not.

Read more: AI Overviews: What They Are and How to Appear in Them

Claude (Anthropic)

What It Is

Claude is Anthropic’s AI assistant, known for its emphasis on accuracy, safety, and nuanced reasoning. Claude is increasingly used by UK professionals who prioritise reliable, well-reasoned answers — particularly in regulated sectors like law and finance.

How It Generates Answers

Claude generates answers from its training data, which includes a broad corpus of web content, books, and academic material. Claude does not currently browse the web in real time during standard conversations, which means its citations are drawn entirely from its training knowledge.

How It Cites Sources

Claude attributes information to sources when it can identify them with confidence, but its citation behaviour is more conservative than Perplexity’s. It tends to reference well-known publications, institutions, and established brands rather than providing direct links.

What Earns Citations

UK Usage

Claude’s UK user base is smaller than ChatGPT’s but concentrated among professionals in legal, financial services, and research roles — sectors where accuracy and reasoning quality are prioritised over speed.

Cross-Platform Strategy

A robust GEO strategy does not optimise for a single platform. It builds the underlying authority signals — entity strength, content citability, structural clarity, and source trust — that all four platforms value, while accounting for platform-specific differences in citation behaviour.

Key resources for building a cross-platform strategy:

MarGen’s Approach

MarGen’s Synaptic Authority Engine methodology is designed to build citation authority across all four platforms simultaneously. We audit your current visibility on each platform, identify the gaps, and build a programme that systematically closes them.

Request your free AI Visibility Audit to see where your brand currently appears — and where it does not — across ChatGPT, Perplexity, Google AI Overviews, and Claude.