Module 1 · How answer engines decide · Lesson 3

Answer engines compared

ChatGPT, Gemini and Google's AI features, Perplexity, Claude and Copilot each find and show sources differently. Results from one do not transfer to another.

5 min

Ce cours n'est pour l'instant disponible qu'en anglais. Le reste du site est en français.

In this lesson

  • Know how each major engine tends to show its sources
  • Understand why a result in one engine says little about another
  • Choose which engines to track first for your audience

Each answer engine has its own index, its own way of deciding when to search and its own way of showing sources. A brand recommended in one can be absent from another for the same question. Track the engines your buyers actually use, check each one separately, and expect the details below to change: these products are updated often.

Answer engines and how they show sourcesChatGPT: Usually, when it searches. Google AI Overviews and AI Mode: Yes, linked sources. Gemini: Sometimes, when grounded in search. Perplexity: Yes, prominently. Claude: When web search is enabled. Copilot: Yes, alongside answers. Qualitative, at the time of writing; check each engine yourself.ENGINESHOWS SOURCES?ChatGPTUsually, when itsearchesGoogle AI Overviews and AIModeYes, linked sourcesGeminiSometimes, whengrounded in searchPerplexityYes, prominentlyClaudeWhen web search isenabledCopilotYes, alongsideanswersshows sourcessometimes, or under conditions
ChatGPT
Shows citations?
Usually, when it searches
Typical use
General questions, research, comparisons
What to check first
Whether your pages appear as sources on searched answers
Google AI Overviews and AI Mode
Shows citations?
Yes, linked sources
Typical use
Questions asked in Google Search
What to check first
That your key pages are indexed and eligible in Google Search
Gemini
Shows citations?
Sometimes, when grounded in search
Typical use
Assistant-style questions
What to check first
How it describes your brand without a search
Perplexity
Shows citations?
Yes, prominently
Typical use
Research-style questions
What to check first
Which of your pages, if any, are read
Claude
Shows citations?
When web search is enabled
Typical use
Analysis, writing, research
What to check first
Accuracy of the brand description from model knowledge
Copilot
Shows citations?
Yes, alongside answers
Typical use
Work and search questions
What to check first
Results grounded in a different index from Google's

The engines, one at a time

ChatGPT

ChatGPT answers from model knowledge and, when it decides a question needs current information or the user asks it to, searches the web. Searched answers usually carry links to their sources. Its crawlers are documented separately for search and for training, which matters in lesson 7.

Gemini, Google AI Overviews and AI Mode

Google's AI features sit on top of Google Search. AI Overviews appear above classic results for some queries and link to the pages they draw on. AI Mode is a conversational search experience with links in the answer. The Gemini assistant can also ground answers in Google Search. If your pages are not eligible for Google Search, they are unlikely to appear in these features.

Perplexity

Perplexity is built around search. Almost every answer is assembled from retrieved pages and shows its sources prominently, which makes it a useful place to see which of your pages, if any, are being read.

Claude

Claude answers from model knowledge and, where web search is enabled, from pages it retrieves, citing them in the answer. Whether search is on depends on the product and the user's settings, so the same question can behave differently for different people.

Copilot

Microsoft Copilot grounds many answers in web search and shows citations alongside them. It draws on a different search index from Google's, which is one reason results do not match across engines.

Answer engines at a glance (qualitative, check yourself)
EngineShows citations?Typical useWhat to check first
ChatGPTUsually, when it searchesGeneral questions, research, comparisonsWhether your pages appear as sources on searched answers
Google AI Overviews and AI ModeYes, linked sourcesQuestions asked in Google SearchThat your key pages are indexed and eligible in Google Search
GeminiSometimes, when grounded in searchAssistant-style questionsHow it describes your brand without a search
PerplexityYes, prominentlyResearch-style questionsWhich of your pages, if any, are read
ClaudeWhen web search is enabledAnalysis, writing, researchAccuracy of the brand description from model knowledge
CopilotYes, alongside answersWork and search questionsResults grounded in a different index from Google's

Why one result set does not transfer

Three things differ between engines: the index each one searches, the rules each one uses to decide when to search at all, and the sources each one tends to trust. A page that is well indexed in one search engine may be thin or missing in another. A brand that is well represented in training data may still lose a searched answer to a fresher page. That is why a single blended score across engines is less useful than a per-engine view.

When engines disagree about you

Disagreement between engines is a clue, not noise. If one engine describes you correctly and another does not, compare the sources each one shows. Often the wrong answer traces back to a single outdated page: an old directory listing, a stale review profile or a press article about a product you have since renamed. Fixing that source can correct more than one engine at once.

Worked example: Northwind Dental

Northwind asks its reception team which tools patients mention. Most say they searched Google; a few younger parents mention ChatGPT. Northwind tracks Google AI Overviews and ChatGPT first. In Google's answer it is mentioned through its map profile; in ChatGPT it is not mentioned at all for the same question, because the searched answer leans on a directory page where Northwind's listing is incomplete. Two engines, two different fixes.

Key takeaways

  • Each engine has its own index, search rules and way of showing sources.
  • A result in one engine says little about another; report engines separately.
  • Start with the engines your buyers actually use, and re-check behaviour regularly because products change.

Practice task

Adds to your plan: How answer engines decide for us

  1. Ask five recent customers, or your sales and support teams, which assistants buyers mention.
  2. Pick two or three engines to track first and write one sentence on why each matters.
  3. Ask your top buyer question in each one and note how each shows its sources.
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Knowledge check

Three questions. Pick an answer to see whether it is right and why.

1. Your brand is recommended in Perplexity. What does that tell you about ChatGPT?
2. Which engines are most tied to Google Search eligibility?
3. How should you choose which engines to track first?