What Is Google PageRank, How Is It Earned & Does It Matter in 2016? was originally published on BruceClay.com, home of expert search engine optimization tips.
Editor’s note: This article was updated in June 2016 to reflect the latest SEO understanding of Google PageRank.
When a user enters a search query, the search engine’s number one goal is to return results that are high-quality, relevant and able to best give them what they want. One of the 200+ factors Google takes into consideration to determine which webpages best fit the bill is PageRank.
What is PageRank?
PageRank (PR) is a calculation, famously invented by Google’s founders Larry Page and Sergey Brin, which evaluates the quality and quantity of links to a webpage to determine a relative score of that page’s importance and authority on a 0 to 10 scale.
The top sites set the bar, so to speak, and the 10-point scale plummets exponentially down from there.
PageRank 5 websites have a good number of inbound links, PR 3 and PR 4 sites have a fair amount, and brand new websites without any inbound links pointing to them start at PageRank 0.
NOTE: You may be curious what your site’s or your competitor’s PR score is. But Google no longer reveals the PageRank score for websites. It used to display at the top of web browsers right in the Google Toolbar, but no more. And PR data is no longer available to developers, either. Even though it’s now hidden from public view, however, PageRank remains an important ingredient in Google’s secret ranking algorithms.
Since Google wants to return page one results that are high quality, relevant, and trustworthy, it may return webpages with better PageRank scores higher up in the SERPs, although PageRank is only one of many ranking factors taken into consideration.
Since PageRank is only one factor in the Google ranking algorithm, it’s important to remember that a high PageRank does not guarantee high rankings — but it can significantly help.
What Is “Link Juice” and What Are PageRank “Points”?
When Site A links to your webpage, Google sees this as Site A endorsing, or casting a vote for, your page. Google takes into consideration all of these link votes (i.e., the website’s link profile) to draw conclusions about the relevance and significance of individual webpages and your website as a whole. This is the basic concept behind PageRank.
When a website links to your site, or when you link internally from one of your pages to another, the link passes PageRank points. This passing of PageRank points is also commonly called “link juice” or “link equity” transfer.
The amount of link juice passed depends on two things: the number of PageRank points of the webpage housing the link, and the total number of links on the webpage that are passing PageRank. It’s worth noting here that while Google will give every website a public-facing PageRank score that is between 1 and 10, the “points” each page accumulates from the link juice passed by high-value inbound links can — and do — significantly surpass ten. For instance, webpages on the most powerful and significant websites can pass link juice points in the hundreds or thousands. To keep the rating system concise Google uses a lot of math (ask in the comments if you want to hear about it) to correlate very large (and very small) PageRank values with a neat and clean 0 to 10 rating scale.
How Link Juice Is Passed
Think of it this way: Every webpage has a limited amount of link juice it can pass, and the top of that limit is the total PageRank points that page has accrued. So, a webpage with 20 accrued PageRank points cannot pass more than 20 points of link juice per page.
If a page with 20 PageRank points links to one other page, that one link will transfer the full amount of link juice to that one other webpage. But if a page with 20 PageRank points links to five webpages (internal or external), each link will transfer only one-fifth of the link juice.
Google applies a decay value to every pass, so the actual numbers will be a little less than our diagram shows below. But to explain the PageRank concept simply, the formula is PR points divided by number of on-page links, or in this case, 20 divided by five:
What if you want to link to several resources to aid user experience, but you have a strategic reason to withhold passing PageRank to those pages?
You can tell Google not to pass PageRank by amending some links with a rel=”nofollow” attribute. A nofollowed link is not crawled by the search engines, and no PageRank or anchor text signals are transferred.
However, Google still sees nofollowed links as part of the total number of links on the page. The PageRank value available to pass through the remaining, followed links is thus reduced.
So for example, if you have a PageRank 18 webpage with 100 PR points that has four links on a page, and three of those links have rel=”nofollow” tags, the one link that doesn’t have rel=”nofollow” will probably pass only one-fourth, or 25 points, of link juice. (Find out when nofollow is essential below.)
Transferring PageRank/Link Juice with Internal Linking
You can help Google see pages of your website as subject matter authorities by linking to your own important pages from related articles.
For instance, if you have an article called “How To Do Keyword Research,” you can help reinforce to Google the relevance of this page for the subject/phrase “keyword research” by linking from an article reviewing a keyword research tool to your How To Do Keyword Research article. This linking strategy is part of effective siloing, which helps clarify your main website themes.
When Nofollow Is Essential
Adding rel=”nofollow” to a link may not conserve PageRank, as SEOs once used it to sculpt the flow of PR value through a site (aka “link sculpting”). Still, nofollow is essential for certain types of links:
- Paid links and ads
- Links that would dilute your subject relevance
- Links to untrustworthy pages
Paid-for links and ads on your site MUST have a nofollow attribute (see Google’s policy on nofollow). If you have paid links that are left followed, the search engines might suspect you are trying to manipulate search results and slap your site with a ranking penalty. Google’s Penguin algorithm eats manipulative paid links for lunch, so stay off the menu by adding nofollow attributes where applicable.
Nofollow is also essential on links to off-topic pages, whether they’re internal or external to your site. You want to prevent search engines from misunderstanding what your pages are about. Linking relevant pages together reinforces your topic relevance; to preserve your silos, strategic use of the nofollow attribute can be applied when linking off-topic pages together.
A third case Google gives for using nofollow is for untrustworthy sites. Of course, you wouldn’t want to pass PageRank to a sketchy site.
A word of caution: Now that you understand basically how PageRank works, we don’t want to give you the wrong idea. It’s not true that the more links you have, the better off you are.
In today’s world, QUALITY is more important than quantity. Google penalties have caused many website owners to not only stop link building, but start link pruning instead. Poor quality links (i.e., links from spammy or off-topic sites) are like poison and can kill your search engine rankings. Only links from quality sites, and pages that are relevant to your website, will appear natural and not be subject to penalty. So never try to buy or solicit links — earn them naturally or not at all.
Want to know more? Learn more about link pruning, the action you take when links from low quality pages are giving Google the wrong idea about your website.