Key takeaways
PageRank is an algorithm used by Google Search to rank web pages by treating each link as a vote of confidence. Created by Larry Page and Sergey Brin at Stanford in 1996, it scores a page on the number and quality of pages linking to it, passing authority through links and dampening it by a factor of about 0.85. Google retired the public PageRank score in 2016 but still uses the concept internally.
- PageRank measures a web page's importance by the quantity and quality of inbound links, where links from high-authority pages count for more.
- It was invented by Larry Page and Sergey Brin at Stanford University in 1996 as the BackRub research project, and named after Larry Page.
- The model uses a damping factor of about 0.85, simulating a random surfer who keeps clicking links 85 percent of the time and jumps to a random page 15 percent of the time.
- Google stopped showing the public Toolbar PageRank score on April 15, 2016, but confirms PageRank is still used internally as one of many ranking signals.
- The original US patent 6,285,999 was assigned to Stanford University; all PageRank patents had expired by 2019.
What is PageRank?
Definition
PageRank is an algorithm used by Google Search to rank web pages in search results by measuring the number and quality of links pointing to each page. It treats a hyperlink from one page to another as a vote of confidence, and weights those votes by the importance of the page casting them. A link from a highly trusted page passes more value than a link from an obscure one.
The algorithm assigns every page a numerical score, the PageRank, between 0 and 1, representing the probability that a person randomly clicking links would land on that page. Pages that accumulate many high-quality links earn higher scores and tend to rank higher. PageRank evaluates the link graph of the entire web, not the content of any single page, which is why it works alongside hundreds of other ranking signals rather than on its own. For the foundations of earning those links, see our guide to link building best practices.
PageRank at a glance
- Created by
- Larry Page and Sergey Brin
- Origin
- Stanford University, 1996 (BackRub)
- Damping factor
- About 0.85
- Score range
- A probability between 0 and 1
- Patent
- US 6,285,999, expired by 2019
- Public score retired
- April 15, 2016
- Status today
- Still used internally by Google
- Core idea
- Links are votes weighted by authority
How does PageRank work?
PageRank works on a simple idea called the random surfer model. Imagine a person who starts on a random web page and keeps clicking links at random. PageRank is the long-run probability that this surfer ends up on any given page. Pages that are easy to reach through links accumulate higher probability and therefore higher PageRank.
The score of a page is the sum of the PageRank passed to it by every page that links to it. Critically, a linking page does not pass its full score to each target. It divides its PageRank evenly across all of its outbound links, so a page with many outbound links passes less value through each one. This is why a single link from a focused, authoritative page can outweigh dozens of links from pages that link out indiscriminately.
The PageRank formula and the damping factor
The simplified PageRank of a page is the sum, over every page linking to it, of that linking page's PageRank divided by its number of outbound links. Written plainly: PR(u) equals the sum of PR(v) divided by L(v), for every page v that links to u, where L(v) is the count of links on v.
The full formula adds a damping factor, usually set to about 0.85, to model the chance that a surfer stops following links and jumps to a random page instead. The probability of continuing to click is the damping factor d, and the probability of jumping randomly is 1 minus d. The formula becomes PR(A) equals (1 minus d) divided by N, plus d times the sum of incoming PageRank shares, where N is the total number of pages. The 0.85 value means the surfer keeps clicking roughly 85 percent of the time and teleports to a random page about 15 percent of the time, which keeps the math stable and prevents isolated pages from trapping all the score.
History of PageRank: a timeline
PageRank evolved from a 1996 Stanford research project called BackRub into the algorithm that launched Google and, eventually, a metric Google stopped showing the public.
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1996
BackRub research project begins
Larry Page and Sergey Brin develop PageRank at Stanford University as a research project initially called BackRub, which analyzed the web's back-link structure.
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1998
Foundational papers and Google founded
Page and Brin publish the papers describing PageRank and Google's prototype, including The Anatomy of a Large-Scale Hypertextual Web Search Engine, and found Google.
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2001
PageRank patent granted
US patent 6,285,999, covering the method behind PageRank, is granted on September 4, 2001 and assigned to Stanford University, which licensed it exclusively to Google.
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2009
PageRank removed from Webmaster Tools
Google removes the PageRank metric from its Webmaster Tools, an early step in retiring the public-facing score.
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2016
Public Toolbar PageRank disabled
On April 15, 2016, Google turns off the display of PageRank data in the Google Toolbar, ending public access to the green PageRank bar.
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2019
All PageRank patents expire
By 2019 the patents underlying PageRank, including US 6,285,999, have expired, though Google continues to use the concept internally as a ranking signal.
Who created PageRank and why does the name matter?
PageRank was created by Larry Page and Sergey Brin at Stanford University in 1996, while they were PhD students. Their research project was originally called BackRub, because it analyzed the back links pointing to a page. The work was first described publicly in two papers, including The Anatomy of a Large-Scale Hypertextual Web Search Engine, which introduced Google's prototype.
The name PageRank is a deliberate play on words. It references both the web page being ranked and the surname of its co-creator, Larry Page. The underlying insight drew on decades of earlier work in citation analysis, where the importance of an academic paper is judged partly by how many other papers cite it. Page and Brin applied the same logic to hyperlinks, turning the chaotic structure of the web into a measurable ranking signal.
Is PageRank still used today?
Yes, but not in the form most people remember. Google retired the public Toolbar PageRank score, the green 0-to-10 bar that webmasters once obsessed over, removing it from Webmaster Tools in 2009 and turning off its display in the Google Toolbar on April 15, 2016. The public number is gone for good.
The underlying algorithm, however, lives on. Google has confirmed that PageRank, in an evolved internal form, remains one of the many signals it uses to rank pages. It is no longer the dominant factor it was in Google's early years, because the modern ranking system blends content relevance, page experience, freshness, and machine-learned signals. But the core principle, that links from trusted pages signal authority, still shapes search results and informs link-based SEO strategy today. To balance authority with the on-page experience signals that now sit beside it, see our guides to E-E-A-T and Core Web Vitals.
PageRank versus modern ranking signals
PageRank measures one thing: link authority. Modern search ranking weighs far more. It is useful to see where PageRank sits among the broader signal set so you do not over-invest in links at the expense of everything else.
| Signal | What it measures | Relative weight today |
|---|---|---|
| PageRank (link authority) | The quantity and quality of inbound links to a page | One input among hundreds, not the deciding factor |
| Content relevance and helpfulness | Whether the page is original, comprehensive, and people-first | Grown in importance via Helpful Content guidance |
| Page experience | Core Web Vitals such as loading, interactivity, and stability | A tiebreaker when other factors are close |
| Topical authority and E-E-A-T | Experience, Expertise, Authoritativeness, and Trust of the source | Shapes whether a source deserves visibility at all |
The practical takeaway is that earning links from relevant, authoritative sites still helps, but it works only when the linked page genuinely deserves to rank on its own merits.
How to optimize for PageRank
To optimize for PageRank, earn editorial links from authoritative and relevant pages, distribute that authority with clean internal linking, and avoid manipulative schemes that Google's link spam systems devalue.
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Earn links from authoritative, topically relevant pages
PageRank weights links by the importance of the page linking to you, so one link from a trusted, relevant source outranks many links from weak or unrelated pages.
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Build a clear internal linking structure
PageRank flows through internal links too, so linking from high-authority pages to important pages helps distribute ranking value across your own site.
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Create content genuinely worth linking to
Original research, data, and comprehensive guides attract editorial links naturally, which is the only durable way to accumulate the link authority PageRank rewards.
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Avoid manipulative link schemes
Google's link spam systems devalue purchased or artificial links, and the ranking value those links would have passed is discounted or penalized.
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Use link attributes correctly
Marking sponsored or user-generated links with rel=sponsored or rel=ugc keeps your link profile honest and avoids passing ranking signals where you should not.
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Reclaim and consolidate authority
Fixing broken inbound links and redirecting retired URLs preserves the PageRank those pages had already earned instead of letting it leak away.
PageRank myths vs. reality
Few SEO topics carry as much outdated folklore as PageRank. Here are the most common myths and what is actually true.
Myth PageRank no longer exists because Google killed the toolbar.
Reality Google retired only the public Toolbar PageRank score in 2016. The underlying algorithm, in an evolved form, is still used internally as one of Google's ranking signals.
Myth More links always mean a higher ranking.
Reality PageRank weights links by the authority of the linking page and divides value across its outbound links. A handful of strong, relevant links beats hundreds of weak ones.
Myth PageRank is the main factor that decides Google rankings.
Reality PageRank was central in Google's early years, but modern ranking blends content relevance, helpfulness, page experience, and machine-learned signals across hundreds of factors.
Myth The PageRank score is a number from 0 to 10.
Reality The 0-to-10 scale was only the public Toolbar approximation. The actual algorithm produces a probability between 0 and 1 representing how likely a random surfer is to land on a page.
Myth You can buy your way to high PageRank with paid links.
Reality Google's link spam detection devalues paid and manipulative links, so they pass little or no PageRank and can trigger penalties that hurt rather than help.
Frequently asked questions
PageRank is Google's algorithm for scoring how important a web page is, based on the number and quality of links pointing to it. It treats each link as a vote, and votes from trusted pages count for more. Higher PageRank pages tend to rank better in search results.
PageRank was invented by Larry Page and Sergey Brin, the founders of Google, while they were PhD students at Stanford University in 1996. The algorithm was named after Larry Page, and it began as a research project originally called BackRub before Google launched.
The damping factor, usually set to about 0.85, models the chance that a random surfer keeps clicking links rather than jumping to a random page. It means the surfer continues clicking roughly 85 percent of the time, which keeps PageRank scores mathematically stable across the web.
Yes. Google retired the public Toolbar PageRank score in 2016, so users can no longer see it. However, Google has confirmed that the PageRank algorithm, in an updated internal form, is still one of the many signals it uses to rank pages in search results today.
You cannot check a true PageRank score anymore. Google disabled the public Toolbar PageRank display on April 15, 2016, and any third-party tool claiming to show real PageRank is using its own estimate. Use authority metrics like Ahrefs Domain Rating as a proxy instead.
PageRank is Google's internal link-based algorithm and is no longer publicly visible. Domain authority metrics like Moz DA or Ahrefs Domain Rating are third-party scores built by SEO tools to estimate link strength. They approximate PageRank's logic but are not Google's actual numbers.
Yes. The method behind PageRank was covered by US patent 6,285,999, granted in 2001 and assigned to Stanford University, which licensed it exclusively to Google. All PageRank patents had expired by 2019, so the technique is no longer patent-protected.
The name is a play on words referencing both the web page being ranked and the surname of co-creator Larry Page. It also nods to citation analysis in academia, where a paper's importance is judged by how many other papers cite it, applied here to hyperlinks.
The bottom line
Bottom line
PageRank turned the link structure of the web into a measurable signal of trust, and that core idea still holds: links from authoritative, relevant pages remain a genuine ranking advantage. The green toolbar number is gone, but the algorithm endures inside Google as one signal among many. Earn real editorial links, route authority cleanly through your own site, and pair link strength with content that deserves to rank.
References
- PageRank - Wikipedia
- The Anatomy of a Large-Scale Hypertextual Web Search Engine (Brin and Page, Stanford)
- US Patent 6,285,999 - Method for node ranking in a linked database
- In-depth guide to how Google Search works - Google Search Central
- Creating helpful, reliable, people-first content - Google Search Central
- Google link spam and link best practices - Google Search Central