Before you allocate engineering time to AI visibility, you need to understand the platform economics. AI platforms collectively drive only 1% of total web traffic — Conductor measured 3.3 billion sessions between May and September 2025 — yet those visitors convert at roughly 3x the rate of search visitors, according to a Microsoft Clarity study across 1,200+ publisher sites. That tension is the resource allocation puzzle this article resolves.
Not all AI platforms are equal. ChatGPT dominates referral volume at 87.4% of all non-Google AI traffic. Perplexity leads on crawl efficiency. Gemini is the fastest-growing at 388% year-over-year. Microsoft Copilot converts B2B subscriptions at 17x the direct traffic baseline. And Anthropic Claude crawls your infrastructure at up to 500,000 pages per referred visitor.
Underpinning all of this is a metric Cloudflare coined: the crawl-to-refer ratio. It measures how much each platform takes from your infrastructure versus what it sends back — ranging from Anthropic’s 500,000:1 peak to Microsoft’s 40.7:1. It is the signal that separates platforms worth optimising for from those worth blocking, a distinction the broader discovery funnel shift makes increasingly consequential.
How much referral traffic do AI platforms actually send to websites?
About 1%. That is the honest starting point before any platform-specific claim can mean anything.
Conductor measured 1.08% across 13,770 domains and 3.3 billion sessions from May to September 2025. SE Ranking found 0.15% globally across January to April 2025, up from 0.02% in 2024. TollBit‘s Q2 2025 report puts it bluntly: Google delivers 831 times more visitors than all AI systems combined.
The growth is real, though. SE Ranking’s 7x increase over one year shows these are not static figures. And Conductor found the IT vertical receives 2.8% AI referral share — the highest of any industry. If you are building software products, you are already in the highest-opportunity segment.
Small today, growing quickly, concentrated in technology. Everything that follows is about how to optimise within that 1% — not a claim that AI is about to displace Google.
Which AI platform sends the most referral traffic — ChatGPT, Perplexity, or Gemini?
ChatGPT, by a wide margin. Conductor found it responsible for 87.4% of all AI referrals. SE Ranking’s independent measurement puts it at 77.97% of global AI platform traffic. The Ahrefs January 2026 cohort logged ChatGPT at 3.3 million visits, growing at +9.2% month-over-month.
The referral mechanism matters here. It is SearchGPT mode that generates clicks, not standard conversational ChatGPT. When SearchGPT surfaces citations, 50% point to business and service websites (Profound). ChatGPT users click 1.4 external links per visit on average, compared with 0.6 for Google users (Momentic, 2025). Session duration from referred visitors averages close to ten minutes — these are not casual arrivals.
The cost side: GPTBot‘s share of all AI crawling grew from 4.7% to 11.7% between July 2024 and July 2025 (Cloudflare), and the crawl-to-refer ratio averaged 1,437:1. Volume dominance comes with infrastructure cost. One lever worth knowing for larger publishers: TollBit found OpenAI content licensing deals produce 88% more scraping and significantly stronger referral rates. The terms are negotiable.
How does Perplexity AI compare on referral quality and crawl efficiency?
Perplexity holds 15.10% of global AI traffic (SE Ranking, January–April 2025) and 19.73% in the US — meaningfully higher than its global share. If your B2B SaaS audience is US-concentrated, that gap matters.
The crawl-to-refer ratio is where Perplexity really stands out. Cloudflare’s July 2025 data shows 194:1, versus OpenAI’s 1,437:1 and Anthropic’s 38,065:1. The ratio has risen from 54.6:1 in January 2025 — worth watching — but the absolute comparison still favours Perplexity clearly.
Session duration averages around nine minutes (SE Ranking), comparable to ChatGPT. There is also a direct optimisation lever that other platforms do not offer: Perplexity is built around citing sources, and it favours authoritative content with original data. If your content strategy produces proprietary benchmarks or technical analysis, that mechanism responds directly to those investments.
One caveat: several publishers told Digiday that Perplexity is “one of the most badly-behaved” crawlers, apparently using headless browsers rather than conventional bot methods. Crawl efficiency and crawl behaviour are separate dimensions.
Is Google Gemini’s 388% referral traffic growth actually meaningful?
The headline needs base-rate context. Gemini currently holds 6.40% of AI platform traffic globally (SE Ranking, January–April 2025), versus ChatGPT’s ~78%. The January 2026 Ahrefs cohort recorded Gemini at 196,700 visits. 388% growth from that base is still a small number.
The trajectory is sustained though: +31.7% month-over-month in November–December 2025, then +53.1% in January 2026. Gemini’s desktop visits doubled between August and November 2025 while ChatGPT’s rose around 1% (Sensor Tower).
The forward-looking signal is the gap between Gemini’s 346 million monthly active users and its current referral conversion rate. When citation features mature — which the month-over-month acceleration suggests is underway — the headroom is real. When Gemini does refer visitors, conversion quality is respectable: 4x direct traffic baseline (Microsoft Clarity), third highest among AI platforms.
The practical read: 388% growth is a quarterly monitoring signal, not a current investment priority. 6.4% share does not justify dedicated resources for most teams relative to ChatGPT or Perplexity.
Why does Microsoft Copilot have the highest B2B conversion rate among AI platforms?
Microsoft Copilot converts subscription traffic at 17x the rate of direct traffic — highest of any platform in the Microsoft Clarity study. Perplexity converts at 7x baseline. Gemini at 4x. Copilot also converts at 15x the rate of search traffic. Nothing else in the dataset comes close for subscription-based business models.
The reason is ecosystem pre-qualification. Copilot users are already inside Microsoft enterprise workflows — Teams, Office 365, Azure. When one clicks through to a B2B SaaS product, they arrive already in a procurement context and familiar with the product category. The conversion premium is structural, not accidental.
The crawl efficiency matches. Microsoft’s crawl-to-refer ratio averaged 40.7:1 in July 2025 (Cloudflare) — low ratio, predictable behaviour through unified Bingbot infrastructure rather than a proliferating set of separate bots.
Volume relative to ChatGPT is small. But if your buyers are in the Microsoft enterprise stack, deprioritising Copilot in favour of higher-volume platforms is a misallocation.
Does AI referral traffic actually convert better than search traffic?
Yes — with some caveats about where the data comes from.
The Microsoft Clarity study across 1,200+ publisher sites found LLM sign-up conversion at 1.66% versus search at 0.15% and social at 0.46%. For subscriptions, LLM conversion was 1.34% versus search at 0.55%. The “3x” headline is against the blended channel average; for sign-ups specifically, the multiple versus search is closer to 11x.
Multiple independent sources support the direction. SE Ranking found AI visitors spend 67.7% more time on site than organic search visitors — 9 minutes and 19 seconds versus 5 minutes and 33 seconds. Adobe Analytics shows 8% longer visits, 12% more pages per session, and 23% lower bounce rate. Semrush puts the average AI search visitor at 4.4x the value of a traditional organic visitor.
The mechanism is intent pre-qualification. Before clicking through, the user has already had a conversational exchange that refined their query. They arrive with more specific intent than someone who typed into Google and clicked the first result — a structural difference in how they were filtered before reaching your site.
The caveat: the Clarity finding is from publisher sites, not B2B SaaS specifically. Zero-click and the Great Decoupling provides the important backdrop here — high-converting traffic is only valuable if it continues to exist. Treat the 3x as directionally correct and validate it with your own analytics.
What does the crawl-to-refer ratio reveal about AI platform value extraction?
The crawl-to-refer ratio — coined by Cloudflare — measures how many pages an AI platform’s crawlers visit per single human visitor referred back to your site. Think of it as a producer/consumer ratio. It quantifies the value extraction imbalance directly.
Anthropic is the extreme anchor case. Cloudflare’s Year-in-Review showed the ratio peaking at 500,000:1. By January 2025 it was 286,930:1. By July 2025: 38,065:1 — an 87% decline in six months, after Anthropic added web search to Claude in March 2025, creating referral pathways that previously did not exist. ClaudeBot is now the second-largest AI-only crawler by traffic share and still sends almost no traffic back.
Here is the full Cloudflare Radar dataset from January to July 2025:
Anthropic — January 2025: 286,930:1 | July 2025: 38,065:1 | Change: −87%
OpenAI — January 2025: 1,217:1 | July 2025: 1,091:1 | Change: −10%
Perplexity — January 2025: 55:1 | July 2025: 195:1 | Change: +256%
Microsoft — January 2025: 39:1 | July 2025: 41:1 | Change: +5%
Google — January 2025: 4:1 | July 2025: 5:1 | Change: +43%
Source: Cloudflare Radar, January–July 2025. Google’s ratio reflects its unified search infrastructure — Googlebot serves both organic search and Gemini crawling simultaneously — and is not comparable to standalone AI referral economics.
Two things to note. First, trajectories matter — Anthropic at 38,065:1 and declining is a different risk profile from that number held static. Second, Microsoft and Google’s low ratios reflect unified crawler infrastructure, not necessarily superior citation practices.
The blocking decision is complicated. TollBit’s Q2 2025 report found 13.26% of AI bot requests already ignore robots.txt (up from 3.3% in Q4 2024), making enforcement imperfect. Cloudflare’s pay-per-crawl initiative offers a middle path — charge for access rather than blocking outright. As Cloudflare put it: “The Web now stands at a fork in the road. Either a new balance emerges — one where the new AI era helps sustain publishers and creators — or AI turns the open web into a one-way training set.”
For the attribution infrastructure to measure all of this properly, our guide on measuring which platform is sending what has the implementation detail.
What happens to paid search when Google AI Overviews appear on the same query?
Seer Interactive studied 3,119 search terms across 42 client organisations from June 2024 to September 2025. When Google AI Overviews appear on a query, paid CTR dropped 68% year-over-year — from 19.70% to 6.34%. Organic CTR on the same queries declined 61%.
The inversion is the key finding. When your content is cited within the AI Overview, the penalty reverses: 35% higher organic CTR and 91% higher paid CTR (Seer Interactive). Being cited in an AIO is now more valuable than ranking position one below it.
Pew Research Center (March 2025, 900 participants) confirmed the baseline: click-through rate with an AI summary present is 8%, versus 15% without — a 47% reduction. AI Overviews now appear for approximately 13.14% of all queries, up from 6.49% in January 2025.
For B2B SaaS teams allocating budget to educational and informational queries: high-funnel paid search on AIO-affected queries has gone from 19.70% CTR to 6.34% in fifteen months. The economics of using paid search as a substitute for AI citation strategy have deteriorated sharply.
How should a B2B SaaS team prioritise AI platform investment given these economics?
This is an engineering prioritisation problem. The four axes — referral volume, conversion quality, crawl cost, and optimisation leverage — produce different answers for different business contexts. Here is what the data supports.
Start with Perplexity for authority-driven B2B content. Lowest crawl overhead (194:1), citation-forward design that rewards authoritative data-rich content, strongest US B2B representation (19.73% US share), and 9-minute average session duration. If your content produces original benchmarks or technical analysis, Perplexity’s citation mechanism responds directly to those investments.
Invest in ChatGPT/SearchGPT for volume coverage. 87.4% of AI referrals means ignoring ChatGPT leaves most of the AI referral opportunity untapped. Crawl cost is higher (1,437:1), and SearchGPT mode is the specific mechanism to optimise for. Content licensing with OpenAI — if achievable — measurably improves both citation rates and referral volume.
Prioritise Copilot if your audience is in the Microsoft enterprise stack. 17x subscription conversion rate and 40.7:1 crawl efficiency are unmatched for B2B subscription products. If your buyers live in Teams, Office 365, or Azure, Copilot is likely your highest-ROI citation target regardless of volume.
Monitor Gemini quarterly, do not invest heavily yet. 388% YoY growth and 346 million MAU create future upside, but 6.4% current share does not justify dedicated resources for most teams. Set a threshold: if Gemini reaches 15–20% of AI referral share in your analytics, escalate to active optimisation.
Treat Claude as a crawl-management decision, not a referral strategy. 38,065:1 crawl-to-refer ratio with only 0.17% of global AI traffic (SE Ranking, January–April 2025) means infrastructure cost with negligible return. Rate-limit or selectively block, and review quarterly as the ratio declines.
Implement AI traffic attribution before committing significant budget. You cannot optimise what you cannot measure. Segment AI referral traffic from organic search and look for platform-specific referral sources. Note that ChatGPT app traffic may not carry referrer headers — SearchGPT mode is more reliably trackable. For the full setup, see our guide on measuring which platform is sending what.
Here is the prioritisation summary:
ChatGPT — 87.4% of AI referrals | ~3x average conversion | 1,091:1 crawl ratio (Jul 2025) | SearchGPT citations, structured authoritative content
Perplexity — 15.1% global, 19.7% US | 7x baseline conversion | 194:1 crawl ratio | Original data, authoritative B2B research
Gemini — 6.4% share (growing fast) | 4x baseline conversion | Monitor quarterly | Google ecosystem EEAT signals
Copilot — Small but high-value | 17x baseline conversion | 40.7:1 crawl ratio | Microsoft ecosystem presence
Claude — 0.17% | Negligible conversion | 38,065:1 crawl ratio | Rate-limit or block; review quarterly
Sources: Conductor (May–Sep 2025), SE Ranking (Jan–Apr 2025), Microsoft Clarity (2025), Cloudflare Radar (Jul 2025)
One forward-looking note from Tom Capper at Moz: “The strategic risk is not where AI traffic is today but where it will be when you need 6–12 months of citation authority to be visible.” Early investment in ChatGPT and Perplexity builds the authority that compounds. Waiting until AI traffic is material means starting the authority-building clock late.
For teams ready to move from platform prioritisation to execution, the SEO/AEO/GEO strategy framework maps the optimisation workflows across channels.
Frequently Asked Questions
Does Anthropic Claude send any referral traffic at all?
Technically yes, but in practice almost none. Claude accounts for 0.17% of global AI traffic (SE Ranking, January–April 2025). Anthropic added web search to Claude in March 2025, bringing the crawl-to-refer ratio from a 500,000:1 peak to 38,065:1 by July 2025 — still the most extreme extraction ratio among major platforms. When Claude does refer users, session duration is unusually high: SE Ranking found a global average of approximately 19 minutes, apparently driven by a small cohort of highly engaged super-users. Claude is a crawl-management decision, not a referral traffic source.
Which AI platform is best for B2B SaaS brands specifically?
It depends on your ecosystem and conversion model. Copilot delivers the highest subscription conversion rate (17x baseline) and suits organisations whose audience lives in Microsoft enterprise workflows. Perplexity offers the best crawl efficiency (194:1) and favours authoritative, data-rich B2B content, with 19.73% US share. ChatGPT provides the largest volume (87.4% of AI referrals), with 50% of citations pointing to business and service sites. For most B2B SaaS teams, start with Perplexity and ChatGPT citation optimisation, then layer in Copilot if your audience skews Microsoft enterprise.
Is it worth blocking AI crawlers if they send almost no traffic?
It is a genuine strategic dilemma. Blocking reduces server load — relevant when ClaudeBot operates at 38,065:1 — but 13.26% of AI bot requests already ignore robots.txt (TollBit, Q2 2025), making enforcement imperfect. Anthropic’s trajectory from 500,000:1 to 38,065:1 shows platforms can shift toward better referral rates, so blanket blocking may forfeit future value. Tom Capper at Moz frames it as leverage: “They are not blocking because they think that is a good idea in itself; they are blocking because they want to force the AI companies into a value exchange.” Cloudflare’s pay-per-crawl initiative offers a middle path. The practical approach: allow crawlers from platforms you want citations from, rate-limit those with extreme ratios.
What is the crawl-to-refer ratio and why should I care about it?
It measures how many pages an AI platform’s crawler visits per single human visitor referred back to your site. OpenAI averaged 1,437:1 across January to July 2025. Microsoft held at 40.7:1. Anthropic reached 38,065:1 in July 2025. For any team managing infrastructure costs, those numbers represent fundamentally different server load, bandwidth, and compute cost per referred visitor. The ratio reveals whether an AI platform is a net positive or net negative to your infrastructure economics.
Does the 3x conversion rate apply to all industries or just publishers?
The Microsoft Clarity 3x finding is from 1,200+ publisher and news websites, not B2B SaaS specifically. The underlying mechanism — intent pre-qualification through conversational refinement — applies broadly, but treat the specific multiple as directionally correct rather than precisely applicable. SE Ranking’s session duration data (67.7% longer visits for AI visitors) spans 63,987 websites across industries, providing broader support. Validate the conversion premium with your own analytics before making capital allocation decisions based on published benchmarks.
Are AI referral traffic numbers growing fast enough to matter in 12 months?
SE Ranking measured 7x growth in AI traffic share from 2024 to early 2025. Gemini grew 388% year-over-year from September to November 2025 and +53.1% month-over-month in January 2026. If the 7x annual rate holds, AI could represent 1–2% of total web traffic by early 2027. Combined with the 3x conversion premium, that is potentially material pipeline for high-ACV B2B products. Semrush projects AI search may surpass traditional search by 2028. The citation authority lead time is the strategic risk: visibility takes 6–12 months to build. Starting now means the authority is in place when the volume materialises.
