Ahrefs indexes 28.7 billion filtered keywords across 217 locations and stores 35 trillion live backlinks, anchoring one of the most data-dense marketing platforms on the public web.
The Singapore-headquartered company runs the work on its own hardware: 661,000 CPU cores, 3 PB of RAM, and 503 PB of SSD across 3 locations. Its Yep1 supercomputer delivers 23.32 PFlops of compute, sitting alongside an $900 million estimated cloud-spend avoidance over three years. These figures matter to anyone building an SEO, content, or AI-visibility workflow because they describe how much of the web Ahrefs sees and how fast it resurfaces change.
Key Takeaways
- Ahrefs’ content index holds 20.0 billion content pages and 16 years of historical data, with 10 million pages discovered and 300 million pages updated every 24 hours.
- The backlink index covers 493.9 billion pages and 500.4 million post-vetting domains, refreshed every 15-30 minutes.
- AhrefsBot 7.0 crawls 5 million pages every minute, and Ahrefs renders around 80 million pages per day for JavaScript-inserted links.
- Brand Radar tracks 371 million monthly AI prompts across 7 AI indexes, with AI Overviews alone at 281.9 million monthly prompts.
- According to 6sense, Ahrefs holds 14.38% of the SEO and SEM market with 55,210 companies adopting the platform, second only to Google Ads at 70.73%.
- BuiltWith tracks 186,144 sites running Ahrefs Site Verification meta tags, a much wider footprint than the paying-subscriber base.
- The United States supplies 56.85% of Ahrefs customers, followed by the United Kingdom at 10.66% and India at 7.95%.
Editor’s Choice
- The keyword index reached 28.7 billion filtered keywords plus 110 billion keywords ever seen.
- External backlinks history sits at 35.0 trillion records, the largest live-link index publicly disclosed by any SEO tool.
- Internal backlinks indexed reached 22.21 trillion, exposed without a custom crawl, the only SEO tool where you can access this data without a custom website crawl.
- Ahrefs’ organic search traffic index covers 548 million keywords across 186 locations.
- The paid-search database holds 31 million paid pages, 30 million paid keywords, and 7.1 billion paid ads.
- Ahrefs’ supercomputer Yep1 is rated at 23.32 PFlops, anchoring an in-house hardware footprint of 661,000 CPU cores and 503 PB of SSD.
Recent Developments
- In January 2026, Brand Radar shipped AI Share of Voice distribution and history endpoints, plus Custom prompt packages as a standalone product.
- The Search Demand tab was rebuilt to combine total search volume and search queries in a single view and introduce a Brand name-only mode.
- Web Analytics gained metric filters across reports, and a Page domain filter, alongside Doesn’t start with and Doesn’t end with text-matching modes.
- Site Explorer added page types and categories in backlink reports.
- Site Audit Always-on Audits now run a latest activity feed.
- Bulk AI detection arrived on Pro projects, capped at 1,000 pages per crawl, with Keywords Explorer adding Global terms research and search-volume trend data in exports.
Ahrefs Index Size and Top-Line Infrastructure
- The content index covers 20.0 billion content pages with 16 years of historical data across 217 locations.
- Live backlinks reached 35 trillion and filtered keywords 28.7 billion.
- Monthly AI prompts tracked across Brand Radar reached 371 million, spanning 7 AI indexes.
- In-house hardware totals 661,000 CPU cores, 3 PB of RAM, and 503 PB of SSD across 3 locations.
- The estimated cloud bill avoided by running the platform in-house is $900 million over three years.
- The Yep1 supercomputer runs at 23.32 PFlops.
| Index dimension | Figure (June 2026) |
|---|---|
| Content pages | 20.0 billion |
| Live external backlinks | 35 trillion |
| Filtered keywords | 28.7 billion |
| Monthly AI prompts | 371 million |
| Historical data span | 16 years |
| Locations covered | 217 |
| CPU cores in-house | 661,000 |
| SSD storage | 503 PB |
Source: Ahrefs Big Data page, June 2026
AhrefsBot Crawler Activity
- AhrefsBot 7.0 crawls 5 million pages every minute, which the company describes as one of the most active crawlers on the internet.
- The bot discovers 10 million pages and updates 300 million pages every 24 hours.
- Ahrefs renders around 80 million pages per day to capture JavaScript-inserted links that pure-HTML crawlers miss.
- The backlink index runs on 170 trillion rows in the underlying key-value database, with 5 million pages crawled every minute.
- Both AhrefsBot and AhrefsSiteAudit are recognized as verified good bots by Cloudflare.
- AhrefsBot uses the user-agent Mozilla/5.0 (compatible; AhrefsBot/7.0; +http://ahrefs.com/robot/) and obeys robots.txt plus crawl-delay directives.
AI Visibility Index Breakdown
Brand Radar measures 371 million monthly AI prompts across 7 AI indexes and powers the entities index in Site Explorer. AI Overviews dominate the mix at 281.9 million monthly prompts, more than the other six surfaces combined. The chart-friendly split below is the first segmentation of AI-prompt volume that no competing ChatGPT statistics roundup has published with this granularity.
- AI Overviews lead at 281.9 million monthly prompts.
- AI Mode runs at 19.7 million monthly prompts, roughly an order of magnitude below AI Overviews.
- ChatGPT sits at 14.5 million monthly prompts in Brand Radar’s tracked surface.
- Gemini and Perplexity tie at 14.6 million monthly prompts each.
- Copilot tracks at 13.3 million monthly prompts, with Grok at 13.1 million.
- The aggregate of AI Mode plus ChatGPT plus Copilot plus Gemini plus Perplexity plus Grok is roughly 89.8 million monthly prompts, less than a third of AI Overviews on its own.
By the numbers: Ahrefs Big Data reports AI Overviews at 281.9 million monthly prompts, AI Mode at 19.7 million, and ChatGPT at 14.5 million across 7 tracked AI surfaces. The split shows how concentrated AI search volume still is on a single Google surface, with five rival assistants splitting a much smaller pool.
Ahrefs Keyword Database Geography
The keyword index covers 28.7 billion filtered keywords with 110 billion keywords ever seen across 217 locations. The United States anchors the top of the list, followed by Brazil, the United Kingdom, India, and Germany, a distribution that loosely tracks population-weighted search demand on Google.com and other engines.
- The U.S. keyword index alone holds 2.6 billion keywords, the largest single-country slice.
- Brazil sits at 1.5 billion keywords.
- The United Kingdom holds 1.4 billion keywords, with India at 1.3 billion and Germany at 1.2 billion.
- France, Canada, the Russian Federation, Spain, and Japan range from 1.1 billion down to 816 million keywords.
- Mid-tier markets including Indonesia, Italy, Mexico, Australia, Vietnam, and the Philippines sit between 811 million and 712 million keywords.
| Country | Filtered keywords |
|---|---|
| United States | 2.6 billion |
| Brazil | 1.5 billion |
| United Kingdom | 1.4 billion |
| India | 1.3 billion |
| Germany | 1.2 billion |
| France | 1.1 billion |
| Canada | 1.1 billion |
| Russian Federation | 854 million |
| Spain | 850 million |
| Japan | 816 million |
| Indonesia | 811 million |
| Italy | 804 million |
| Mexico | 776 million |
| Australia | 759 million |
| Vietnam | 726 million |
| Philippines | 712 million |
| Türkiye | 688 million |
| Poland | 687 million |
| Netherlands | 662 million |
| Argentina | 623 million |
Source: Ahrefs Big Data page, Keyword index, June 2026
Backlink Index Composition
Ahrefs runs 35.0 trillion external backlink history records and indexes 493.9 billion pages and 500.4 million post-vetting domains. The link counts grow when internal backlinks are added: 22.21 trillion internal backlinks live in the index alongside the external set, a methodological choice that Ahrefs reports no rival surfaces at the same scale.
- External backlinks history sits at 35.0 trillion records within the live index.
- Internal backlinks reach 22.21 trillion, used inside the URL Rating calculation similar to PageRank.
- Internal backlinks specifically tied to the live index total 28.7 trillion.
- The platform renders around 80 million pages per day to catch JavaScript-inserted links.
- At Ahrefs, we render around 80 million pages per day, the company writes, adding that We’re currently the only SEO tool that renders during our regular crawling of the web.
- Both AhrefsBot and AhrefsSiteAudit are Cloudflare-verified good bots.
Why it matters: Exposing internal-link data is rare among SEO tools and matters because internal links carry most of a site’s PageRank surface area; without them, the platform’s URL Rating would miss the same signal Google uses inside its own ranking systems.
Update Frequency Hierarchy
The Ahrefs Help Center explains how often the data in Keywords Explorer and Site Explorer is updated. The schedule is tiered by popularity and data class.
- The backlink index refreshes every 15-30 minutes.
- SERPs in Keywords Explorer and Site Explorer update anywhere from multiple times a day to once in 1-2 months, depending on keyword popularity.
- High-volume keywords typically refresh every 1-2 days.
- Lower-volume keywords might only be refreshed every few weeks.
- Search volume and CPC are updated every few weeks, and at least once a month for each keyword.
- The Volume metric uses a 12-month average per country.
| Surface | Refresh cadence |
|---|---|
| Backlink index | every 15-30 minutes |
| High-volume SERPs | every 1-2 days |
| Lower-volume SERPs | every few weeks |
| Search volume and CPC | every few weeks to at least once a month |
| Search volume averaging window | 12 months |
Source: Ahrefs Help Center policy article, March 2026
Ahrefs Market Share and Customer Reach
According to 6sense’s 2026 market analysis, Ahrefs holds 14.38% of the SEO and SEM category and counts 55,210 companies as adopters, second behind Google Ads. The reach extends beyond paying subscribers: third-party tracker BuiltWith counts 186,144 sites running Ahrefs Site Verification meta tags, the free identifier many sites install to claim ownership inside Ahrefs Webmaster Tools.
- Google Ads leads the SEO and SEM category at 70.73% market share.
- Ahrefs sits at 14.38% in second place.
- SEMrush holds 6.16% and Yext 3.75%.
- The top three product or service offerings of customers using Ahrefs are SEO (1,329), Digital Marketing (1,048), and Web Development (633).
- The BuiltWith tracker count of 186,144 websites sits well above the estimated paying-subscriber base, reflecting the verification tag’s free tier and Ahrefs Webmaster Tools adoption.
Geographic Customer Distribution
Customer concentration tilts heavily toward English-speaking markets and India. The United States alone supplies the majority share, with the United Kingdom and India rounding out the top three.
- The United States accounts for 56.85% of Ahrefs customers.
- The United Kingdom is next at 10.66%.
- India follows at 7.95%.
- The combined U.S., UK, and India share, the sum of three figures 6sense reports, accounts for the bulk of Ahrefs’ customer base outside the long-tail markets.
AhrefsBot Crawler Policy and Verification
Ahrefs runs two crawlers with distinct user-agent strings and policy stances. Site owners can verify both via Cloudflare’s verified-bots program and reach them through public IP ranges.
- AhrefsBot 7.0 uses the user-agent Mozilla/5.0 (compatible; AhrefsBot/7.0; +http://ahrefs.com/robot/) and powers the database for Ahrefs and the Yep search engine.
- AhrefsSiteAudit 6.1 powers the Ahrefs Site Audit tool, with a desktop string Mozilla/5.0 (compatible; AhrefsSiteAudit/6.1; +http://ahrefs.com/robot/site-audit).
- Both bots obey robots.txt and crawl delay by default and are recognized as verified good bots by Cloudflare.
- Yep is an official participant in the IndexNow protocol, the push-notification system that lets sites alert search engines to fresh content.
- As a good bot, AhrefsBot strictly follows the rules in the robots.txt files, does not trigger ads on websites, and does not add numbers to Google Analytics traffic.
| Crawler | User-agent | Cloudflare verified |
|---|---|---|
| AhrefsBot 7.0 | Mozilla/5.0 (compatible; AhrefsBot/7.0; +http://ahrefs.com/robot/) | yes |
| AhrefsSiteAudit 6.1 | Mozilla/5.0 (compatible; AhrefsSiteAudit/6.1; +http://ahrefs.com/robot/site-audit) | yes |
Source: Ahrefs official Bots page (ahrefs.com/robot), June 2026
Ahrefs in the Broader SEO Landscape
Ahrefs publishes a widely cited SEO statistics roundup that situates its data inside the broader search ecosystem. The figures show how concentrated organic discovery still is on Google despite the rise of AI-generated answers.
- Google holds 90.39% of global search engine market share across all devices, per StatCounter.
- Google maintains a web index of about 400 billion documents, per Zyppy.
- Per Ahrefs’ own research, 96.55% of all pages get zero search traffic from Google.
- Organic CTR on queries with Google AI Overviews fell to 0.61% in September 2025, down 61% from 1.76% in June 2024, per Seer Interactive.
- AI Overviews are associated with a 58% lower average click-through rate for the top-ranking organic page, per Ahrefs.
- Only 1.74% of newly published pages reach the top 10 within a year for at least one keyword, with more than 3 years being typical for top-10 ranking pages.
- 72.9% of pages ranking in Google’s top 10 are more than 3 years old.
Key finding: Ahrefs’ large-scale SEO research finds 96.55% of all pages get zero search traffic from Google and that 87% of marketers surveyed use AI to help create content (769 out of 879 respondents). The two figures together explain why the platform invests so heavily in AI visibility tracking alongside classic search SEO.
Where does Ahrefs get its data from?
Ahrefs runs its own crawlers. AhrefsBot 7.0 and AhrefsSiteAudit 6.1, across the open web 24/7, then merges that data with an index of 35.0 trillion external backlink records and 493.9 billion pages inside Site Explorer. Internal-link data, rendering of around 80 million pages per day for JavaScript content, and the AI Visibility index for Reddit and other AI-cited surfaces round out the data sources.
How often does Ahrefs update its data?
Backlinks refresh every 15-30 minutes. SERPs in Keywords Explorer update anywhere from multiple times a day to once in 1-2 months depending on keyword popularity, with high-volume keywords refreshed every 1-2 days and search volume plus CPC every few weeks to at least once a month.
What Is a Good Ahrefs DR Score?
Ahrefs publishes Domain Rating on a 0-100 scale and uses internal-link signals, 22.21 trillion internal backlinks live in the index, alongside external links to compute it. A practical reading is that DR sits relative to a site’s category: a niche business-to-business publisher might rank in the 40-60 band while large media properties exceed 80. The score is a comparative metric, not an absolute predictor of ranking. Treat any single DR cutoff as a guidance benchmark inside a competitive set rather than a quality threshold on its own; the score moves with the surrounding web, not in isolation.
What Are the Cons of Ahrefs?
Three trade-offs surface across reported usage. First, the entry price is higher than several rivals, useful context against the 6.16% market share held by SEMrush and the long tail of cheaper tools. Second, the crawl cadence for low-volume SERPs runs every few weeks, slower than power users sometimes expect. Third, the AI Visibility index covers 7 AI indexes, a competitive scope but one that newer entrants extend further. None of these is a knock-out problem; they are positioning constraints the buyer should weigh against the platform’s index depth.
Conclusion
Ahrefs this year runs one of the largest publicly disclosed marketing data stacks among private SEO platforms. The keyword index reached 28.7 billion filtered keywords, the backlink index 35 trillion live backlinks, internal-link exposure 22.21 trillion, and crawler throughput 5 million pages every minute. The vertical hardware footprint and the 7-surface AI visibility index extend the platform’s reach into AI-driven discovery alongside classic search, and the next twelve months will hinge on how fast each AI surface scales.