Measure AI visibility

Measure AI visibility: one reading does not hold

Measuring AI visibility means counting how often an engine cites your site in its answers. The trap is that a single reading says almost nothing: our measurements show the sources change from one call to the next. Fast Growth Advisors publishes its method, its cost and its dated readings, with the link to run each search again.

How do you measure AI visibility?

On two grounds at once, and most people look at only one. Here is how we went about it on our own site, with the results as they came out.

The pages, first: what an engine can read of them, which crawlers come to fetch them, and which of them surface in its answers. These are facts that can be fixed.

The market questions, next: what the engine answers when a buyer asks about the category, and whom it gives the floor to. There, nothing is controlled, everything is observed.

The first conditions the second. A page an extractor discards will never be cited, however good it is.

The two are nonetheless fixed in different places, one in the template and the markup, the other in the message and the proof it carries. That is what justifies keeping them apart throughout this page, and never adding them into a single score.

Five instruments, two grounds, one dashboard. Each block in the diagram leads to the part of the page that details it.

What do we look at on our own pages?

Three things nobody looks at: what survives extraction, who actually comes to read us, and which of our pages surface in the answers.

1. What survives extraction

An engine does not read a page, it reads what an extractor pulls out of it. We fetch the page with an AI crawler user agent, exactly what it receives, then run it through the three reference extractors: trafilatura, jusText and Resiliparse. The three pages below belong to software vendors, two in HR software and one in workforce scheduling.

Share of the text present in the served HTML that each extractor keeps. Fetched with the GPTBot user agent on 2 September 2026 by Fast Growth Advisors. The vendors are not named: the point is the mechanism, not them.
PageText servedtrafilaturajusTextResiliparse
HR software vendor A25,387 ch.59 %26 %95 %
HR software vendor B13,425 ch.23 %18 %40 %
Scheduling software vendor12,832 ch.49 %35 %91 %
This page9,671 ch.92 %88 %89 %

On HR software vendor B, trafilatura keeps only 23 % of the served text. Four fifths of what the page says never reaches the engine. And the three extractors do not agree with each other: on that same page one keeps 23 %, another 40 %. Content can therefore reach one engine and vanish from another.

2. Who actually comes to read us

A crawler's declared user agent can be forged in one line. So we check every request against the IP ranges the vendors publish. Here is the result on our own servers, over seven days.

Requests declaring themselves an AI crawler on our servers, seven days to 2 September 2026, checked against the IP ranges published by the vendors. Fast Growth Advisors measurement on its own logs.
Declared agentRequestsDistinct addressesWithin published rangesOutside
OAI-SearchBot4544882372
ChatGPT-User419179410
GPTBot3442528316
Perplexity-User31540315
PerplexityBot20250202

Out of 1,734 requests declaring an agent whose vendor publishes its addresses, 1,615 came from elsewhere, or 93 %. The ones presenting themselves as Perplexity were Google Cloud machines and a hosting provider, while Perplexity publishes only eight addresses.

What this measurement says, and what it does not. It covers our two sites, over seven days, and only the agents whose vendor publishes ranges. A published list can be incomplete or lag behind reality, so an address outside the ranges does not prove an intent to deceive. It does prove that a counter of AI visits built on the declared agent mostly measures something else.

Not all these crawlers want the same thing

Counting them together mixes two subjects with different consequences. Some collect training material, others build a search index, others read a page at the moment a user asks a question.

Role declared by each vendor, and volume observed on our servers over seven days to 2 September 2026. Roles are reported from public documentation, volumes are our measurements.
AgentDeclared roleRequests on our servers
GooglebotSearch index, also feeds AI Overviews1,369
Claude-UserRead triggered by a user455
OAI-SearchBotOpenAI search index454
ChatGPT-UserRead triggered by a user419
GPTBotCollection that may serve training344
Perplexity-UserRead triggered by a user315
ClaudeBotCollection that may serve training249
PerplexityBotSearch index, no training according to the vendor202
meta-externalagentMeta collection178
BytespiderByteDance collection162
ApplebotApple search index162
CCBotCommon Crawl public corpus49

The consequence lands straight in robots.txt. Blocking a training collector costs no citations. Blocking an index crawler or a user-triggered reader removes the site from answers. Many sites block the second kind believing they are blocking the first.

One crawler in twenty hits a dead page

Over the same seven days we counted the share of requests that receive a 404 error. The result varies enormously from one crawler to the next.

Share of requests landing on a page that does not exist, by agent, on our servers, seven days to 2 September 2026.
AgentRequestsShare in 404
CCBot4930.6 %
ClaudeBot24913.3 %
PerplexityBot2026.4 %
OAI-SearchBot4545.3 %
GPTBot3444.9 %
Googlebot1,3691.5 %

The public reference measurement, published in late 2024, reported 34.8 % for OpenAI crawlers against 8.2 % for Googlebot. On our servers it is 4.9 % against 1.5 %. The order is the same, the scale is six times smaller, and that is exactly why a public measurement does not replace your own.

A dead URL is a lost source. The redirect plan, treated everywhere as a technical chore, is therefore a visibility matter.

3. Which pages get picked up, and which never

The question arises page by page, and the answer is surprising. A page with heavy search exposure may never be picked up, while a confidential one may be picked up one time in five.

Six pages of fast-growth.fr. Impressions in generative features over three months according to Search Console, citations according to our question probe, 1 and 2 September 2026.
PageAI impressions over 3 monthsShare of its impressionsCited by the probe
/observatoire/720.6 %no
/en/messaging-audit/1217.9 %yes, 3 readings out of 6
/visibilite-ia/363.0 %yes, on 3 questions
/audit-messaging/44.6 %yes, 6 readings out of 6
/linkedin-algorithm-2026…/201.9 %no
/strategie-de-business-development/00 %no

The Observatory is our most picked-up page, at 20.6 % of its impressions, for 34 impressions in total. The article on the LinkedIn algorithm has 1,043 and is picked up only 1.9 % of the time. Search volume and engine pick-up do not follow each other. A page can also be read without ever being cited, like our consulting page, present in search and absent from every generative answer.

White paper, counting bots →
White paper, the recoverable message →

What do we look at on our market questions?

What the engine writes when it is asked the questions of our category, and whom it gives the floor to instead of us. We put the question, archive the full answer, and keep the link that lets anyone run the search again. Without those three, a report cannot be verified.

4. One reading, in full

Here is one of ours, taken on our own market. Query audit messaging site web B2B, French market, French language, six readings between 1 and 2 September 2026. Google writes an answer to all six and cites our page every time.

The complete reading, rendered as the elements that make it checkable. This is the format we deliver, on our pages as much as on our clients own.
ElementValue
Question, word for wordaudit messaging site web B2B
Market and languageFrance, French
First and last reading1 September 2026 at 18:40, 2 September at 16:36
Number of readings6
Resultcited 6 times out of 6, URL fast-growth.fr/audit-messaging/
Organic position1st
Verification linkrun this search again

Why a single score means nothing

An engine that is asked a question does one of three things, and merging them manufactures a false problem. It answers and cites the site. It answers without citing it. Or it does not answer at all.

The third case is not invisibility, it is an absence of measurement. We met it while building the barometer question set: on business password managers, two different phrasings produced no written answer at all. The category exists, the market is crowded, and the engine writes nothing. Nobody is invisible there, there is nothing to see.

But the costliest trap lies elsewhere. Two pages labelled as cited can be in opposite situations.

Two questions where a single score would give us the same mark. Our measurements on fast-growth.fr, six readings per question, 1 and 2 September 2026.
QuestionLabelCited inWhat it really is
audit messaging site web B2Bcited6 readings out of 6always the same page, /audit-messaging/
audit commercial startup B2Bcited6 readings out of 6three different pages across the readings

A tool measuring once labels both as cited, and it is right both times. What it misses is elsewhere: on the first question Google always takes the same page, on the second it changes and cites the English version three readings out of six. The citation is secured, the page receiving it is not, and those are not the same works to undertake.

How many times must the same question be measured

More than once, and the number depends on the question. We replayed the same question eleven times in a row, seconds apart, on two markets.

Eleven readings of the same question on each market, 1 and 2 September 2026. Our measurements on Google AI Overviews.
Market and questionMedian overlap of sourcesDomains present in all eleven
France, comparatif logiciel sirh pme62 %3 of 10
United Kingdom, best hr software for small business100 %8 of 8

Stability is not a property of the instrument, it is a property of the question. On the UK question the engine returns exactly the same eight domains on every call. On the French one, two domains appear only once out of eleven. Sitting in the core is a position, appearing in the fringe is a passage.

What this measurement says, and what it does not. Two questions, one per market, on Google AI Overviews. It does not say France is unstable and the UK is stable. It says stability is measured question by question, and that we have not repeated the experiment on ChatGPT or Perplexity.

Ranking still decides who gets cited

This is the link everyone looks for between classic search optimisation and AI visibility. We measured it on the fifty barometer questions, comparing the sources Google cites with the organic results of the same query.

Overlap between cited sources and organic results. Google AI Overviews barometer, September 2026 edition, French and UK markets.
What is measuredFranceUnited Kingdom
Answers citing at least one of the top three results96 %not measured this way
Answers citing the first result74 %57.5 %
Cited sources that appear in the ranking70.2 %46.5 %

Ranking well remains necessary, and is no longer enough. Three cited sources in ten appear nowhere in the results of the same query in France, and more than one in two in the United Kingdom. A budget that funds ranking alone therefore leaves part of the ground to others.

Measuring on a single engine is not enough

Before choosing its sources, an engine decides whether to search at all. We put twenty questions to four engines, on two of our domains, and the gap is considerable.

Decision to search and citations issued, across 20 questions put to four engines. Our measurements of 6 August 2026, on fast-growth.fr and nomo-ia.com.
EngineSearches the webCitations issuedOf which to our sites
Perplexity100 %39411
Claude85 %2694
Gemini35 %7110
ChatGPT30 %342

Perplexity issues 394 of the 768 citations recorded, ChatGPT issues 34. The same editorial work therefore does not carry the same value depending on which engine buyers use. And Gemini, which cites five times less than Perplexity, cites us almost as often: an engine volume says nothing about the chances of appearing in it.

What the citations returned

Nothing, and this is the most uncomfortable result on this page. Over the same week our two sites received 1,376 crawler visits whose identity was verified, and 22 fetches triggered by a live user question. A human had therefore asked something, and the engine went to read our pages to answer them.

Not one visitor arrived on our sites from an AI answer. Zero. Citation and visit are two different things, and counting the first to forecast the second means confusing two measurements that do not follow each other. That figure is also a starting line, taken before any work: whatever moves next will be attributable.

5. What do we fix when the measurement is bad?

The two grounds above produce findings. Our audit tool turns them into work. It scores each page across four families and lists, rule by rule, what blocks: a lede too short, a title that does not carry the subject, a FAQ missing from the markup, a paragraph that refers to another without naming it.

On the page you are reading, the audit of 3 September 2026 puts the technical and SEO families above the advised threshold, and GEO below it. We leave that visible rather than remove proof to gain points: the tables add sections without adding questions, which the rule penalises. We preferred the proof to the points.

The four scores change with every edit to the page. Publishing them frozen in a table would mean publishing a stale measurement from the next revision onwards, which is exactly what we criticise in others.

What correction changes, at the scale of a market

These findings are not specific to us. The Message-Market Fit Observatory audits the sites of French startups after fundraising, on a grid of clarity and engine readability.

Message-Market Fit Observatory, second quarter 2026 edition, 369 French post-funding startups.
What is measuredResult
Startups below the critical clarity threshold, set at 37.5 out of 7575.9 %
Average message clarity5.33 out of 10
Readiness to be cited by engines0.91 out of 5, or 18 % of potential
Link between amount raised and message clarityR² = 0.036, in other words none

Three startups in four fall below the threshold, and the money raised changes nothing. The last figure is the most useful: message clarity cannot be bought with a funding round, it has to be worked.

Fixing and verifying are two different jobs

Confusing them wastes time. The first instruments say what to change on a page, today. The second say whether the change produced an effect, weeks later.

The instruments Fast Growth Advisors uses on its own pages as much as on its clients own.
InstrumentFamilyWhat it returns
SEO and GEO auditFixesFour scores per page and the list of findings to handle, rule by rule
Three-extractor benchFixesThe share of text each extractor keeps, and what disappears
Question probeVerifiesWhom the engine cites, on which questions, with the link to run the search again
Server log analysisVerifiesWhich crawlers come, from which addresses, and which are verifiable
Search ConsoleVerifiesImpressions, clicks, and share of impressions in generative features

The cost makes the requirement affordable. With the provider we use, one question costs four thousandths of a dollar, so 0.20 dollar for fifty. We publish that figure because a measurement at that price has no reason to be replaced by an assumption.

The Google AI Overviews barometer, method and editions →
ChatGPT visibility, what the engine sees of your site →
876 impostors, what your AI traffic really hides →

6. Everything we measure, in one place

Here is the complete inventory, with for each line the question it answers and the most recent result. Nothing is estimated, everything can be replayed.

The measurements Fast Growth Advisors keeps on its own sites, September 2026. Each line refers to an instrument described above.
What we measureThe question it answersLatest result
State of each questionDoes the engine answer, and does it cite the site73 readings on our 12 questions: 12 citations, 60 without citation, 1 no answer
Source stabilityDoes a citation hold from one call to the next62 % median overlap in France, 100 % in the UK
Core and fringeIs this a position or a passage3 domains out of 10 present in all eleven readings
Ranking and citation overlapIs ranking well enough to be cited70.2 % in France, 46.5 % in the UK
Engine comparisonWhere content has the best chance768 citations, Perplexity 394, ChatGPT 34
Source compositionWho occupies the ground of a category312 sources, 81 % sites, 15 % video
Language of issued queriesIn which language the engine searches40 queries in French against 34 in English, 100 % English in IT
Extraction by three toolsWhat is left of the page for an engine23 % to 95 % of the served text depending on page and extractor
Composition of served weightDoes weight hurt citability30 % CSS and 23 % SVG on one measured page, with no effect on extraction
Crawler volume by agentWho comes to read, and how often4,358 requests in seven days, Googlebot leading
Crawler identity verificationIs the declared agent the real one93 % outside the ranges published by the vendors
Declared role of each crawlerTraining, index, or read on demand12 agents classified, with their volumes
404 error rate by crawlerHow many visits fall into nothing30.6 % for CCBot, 1.5 % for Googlebot
SEO and GEO audit per pageWhat blocks, rule by ruleFour scores and the list of findings, on every published page
Generative impressionsWhich pages the engine picks up219 impressions out of 4,522, or 4.8 %
Visitors from an AI answerDoes citation bring traffic0 over the week measured
Message-Market Fit ObservatoryWhere an entire market stands369 startups, 75.9 % below the clarity threshold
Cost of measurementWhat it costs to know rather than assume0.004 dollar per question, 0.20 dollar per edition

Eighteen lines, five instruments, and not one substitutes for another. That is what makes a single score impossible: these measures share neither the same unit, nor the same ground, nor the same correction delay.

7. What would the dashboard look like?

Like this. Everything below comes from the measurements described above, on fast-growth.fr, between 1 and 2 September 2026, each block from a different instrument.

AI visibility dashboard, fast-growth.fr, 2 September 2026 Question readings 73 12 questions, six times each It cites us 12 on 2 questions only It answers without us 60 the finding that matters It does not answer 1 nothing to fix here What Google answers on our market The question asked What Google does Whom it cites instead of us comparatif logiciel sirh pme answers without us culture-rh.com, apogea.fr, quel-sirh.fr audit visibilite IA entreprise answers without us natural-net.fr, trouvable.app, iaba.tech audit messaging site web B2B it cites us, 6 of 6 fast-growth.fr meilleur logiciel gestion des conges answers without us combohr.com, culture-rh.com, kelio.com Which of our pages get picked up The page served Cited by the probe Share of its impressions in AI /audit-messaging/ yes, 6 readings of 6 4.6 % /en/messaging-audit/ yes, 3 readings of 6 17.9 % /visibilite-ia/ yes, on 3 questions 3.0 % /observatoire/ never 20.6 %, our record /strategie-de-business-development/ never 0 % How it happens, crawler visits over seven days Googlebot 1,369 Claude-User 455 OAI-SearchBot 454 ChatGPT-User 419 GPTBot 344 Perplexity-User 315 ClaudeBot 249 PerplexityBot 202 The 312 cited sources 312 sources Sites and media, 81 % Video, 15 % Forums and institutional, 4 % Extraction of this page trafilatura 92 % jusText 88 % Resiliparse 89 % Question probe, three-extractor bench, server log analysis and Search Console. No line is estimated, no global score is calculated.

Three levels, in the order a director reads them. At the top, what Google answers on our market and whom it gives the floor to instead of us. In the middle, which of our pages it picks up and which it ignores. Only at the bottom, how it happens: the crawlers that visit, the composition of the sources and what the extractors keep.

The order is not decorative. A dashboard that opens with crawler names makes someone read plumbing when they are trying to find out whether their market knows them.

This dashboard does not exist as a product yet. The four instruments run, the measurements are real, and the screen that assembles them is still to be built. We prefer to show it this way rather than announce a platform that has not shipped. It calculates no global score either, and that is deliberate: a citation, a share of extracted text and a crawler visit do not offset one another.

FAQ

How do you measure AI visibility?

By measuring on two grounds at once. On the pages, what an engine can read of them and which crawlers actually come to fetch them. On the market questions, what the engine answers and whom it gives the floor to. The two are fixed in different places, and the first conditions the second. We set out the method here exactly as we apply it to fast-growth.fr.

Why does a single AI visibility score mean nothing?

Because it adds up situations that are not fixed in the same place. An engine can cite a site, answer without citing it, or not answer at all. The third case is not invisibility, it is an absence of measurement. And two cited pages can be cited once out of six readings or six out of six, which an average score erases.

How much does an AI visibility measurement cost?

Four thousandths of a dollar per question with the provider we use, so 0.20 dollar for fifty questions and roughly two euros a year for a set measured every month. We publish that cost because a measurement at that price has no reason to be replaced by an assumption, nor billed as a technical feat.

What do the engines answer in your category?

The free diagnostic puts five questions from your category to ChatGPT, Perplexity and Google AI Overviews. Answers archived, verification link included, causes read on both the message and the pages.

How we measure AI visibility →