Google’s PageRank is a central part of how the search engine works, yet many people don’t understand the algorithm—even among those working with search engine optimization. Here’s a quick rundown—make sure to learn this if you haven’t already.
PageRank is named after one of Google’s founders, Lawrence Page, and is Google’s way of evaluating pages on the web. Each individual page (not site) is assigned a PageRank based on how many and how strong the pages are that link to it. The PageRank algorithm simply weights each page that Google’s crawlers have found based on how many links point to it and how many links the linking pages themselves have. And so on. For those who want to dive deeper into the algorithm, Larry Page and Sergey Brin’s academic paper on the subject is published here.
How PageRank works
At its core, PageRank is a way of measuring how many links point to a page—both directly and indirectly. Not all links are equal, however. A page that has many links pointing to it will pass more value through its own links. So, a link from a trusted site carries more weight than one from a low-authority site. A link from Regeringen.se (the Swedish government’s website), for instance, will pass more PageRank than one from a random blog, since it has more and stronger incoming links.
What leads to misunderstanding
One thing that has caused confusion over the years is Google’s Toolbar. The toolbar displayed a PageRank value ranging from 1 to 10 with a green meter. What some people didn’t understand is that the green bar wasn’t the actual PageRank, but a visual representation of the real PageRank value.
Historically, the toolbar was updated roughly once per quarter. The data it showed was merely a snapshot—often one or two months old—of the actual data. Additionally, the PageRank shown in the toolbar was compressed into a logarithmic scale to fit within the 1 to 10 range. Real PageRank is not a value between 1 and 10. In recent years, toolbar updates have become highly sporadic. For example, it was updated only once last year, and now Google has announced that the toolbar will likely never receive new data again.
For someone new to SEO, this can be confusing. It takes some mental effort to distinguish between Toolbar PageRank (a temporary snapshot) and actual PageRank (the value Google actively uses). That’s why you sometimes hear people with less SEO knowledge claim that “PageRank is dead.” That’s far from true—PageRank is still very much a part of Google’s algorithm. It’s the green value in the toolbar that’s dead.
Magnus Bråth
CEO
Magnus is one of the world's most prominent search marketing specialists and primarily works with management and strategy at his agency Brath AB.