Google SEO & Search Engine Marketing Services

Domain Juice and Authority

This post is a follow on my domain level metrics post , however you may also want to read Understanding Domain Trust and Authority before reading this post further.

In the last post I explained how PageRank is now also calculated on your domain, giving your domain an overall Rank that helps you rank newer pages faster on Google.

Today I wanted to touch specifically on authority or trust and there is a slight problem with what I am going to talk about, that is, it has not been confirmed by any of the major search engines.

However, most of the leading SEO authorities believe Google and co work out the trust level of a site using the following mechanism;

The theory was first put out their by Yahoo and was named “trust rank” it worked on the idea that all major search engines start their crawl of the web on a trusted domain, such as dmoz or the yahoo directory. Now depending on how far away your site is from these domains, in terms of links, it will determine how much your domain is trusted.

This theory is based on the common presumption that spammers link to spammers.

The following diagram shows how this may look:-

domain trust

The further away you get from that trusted domain the less trust your domain will have. How does Google work out the trust of the Yahoo Directory?? The honest answer is who knows, age, outbound links. Probably a combination of hundreds of factors.

It has also been suggested that there is a mechanism called ‘reverse trust’ which looks at how far away your outbound links are from a spam site. This is why we always need to careful about who we link out to. The person we link to may not be a spam site but some of the people they link to may well be. Don’t be overly worried, remember the search engines have never confirmed this.

Domain Juice

This is a very simple concept and again it works in exactly the same way as PageRank.

The links back to your page give it a “Rank”, they also allow your pages to pass on link juice to another page.

Well… it works exactly the same with domains. Each link pointing to your domain gives the whole domain a rank, as per the previous post, however it also allows your domain to pass on “domain juice” to other domains.

So in the below diagram:

domain juice

The numbers represent the amount of juice each page can pass, all these numbers are put together which gives a total amount of domain juice that can pass.

PR Zero Links

This is one of the reasons you should not worry about getting links from ‘pages’ with zero PageRank. Think about the domain as a whole. How much authority does it carry?

A good example is article marketing – If you write an article publish it on ezinearticles it will no doubt be on a page with zero PageRank, however what domain trust, authority, rank and juice does the ezine articles domain possess???

SEOmoz are the leaders in SEO tools in my opinion and their tool bar allows you to see domain level metrics.

In terms of ezine articles here is how their domain stacks up;

domain level metrics

So is a link from a domain this strong worthless??? I don’t think so.

Understanding trust and rank on a domain level can help you better plan your link building strategy and assist you in getting higher rankings faster.

As always feel free to add to this or ask any questions.

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Author: Tim (254 Articles)

is the owner and editor of SEO wizz and has been involved in the search engine marketing industry for over 9 years. He has worked with multiple businesses across many verticals, creating and implementing search marketing strategies for companies in the UK, US and across Europe. Tim is also the Director of Search at Branded3, a Digital Marketing & SEO Agency based in the UK.


{ 8 comments } August 19, 2009 at 8:12 pm

Thanks for your submission to the Sixty First edition of the Blog Carnival: Blogging. Your post has been accepted and its live:

Chris Anderson March 2, 2010 at 12:50 am

If there is really a “reverse trust” mechanism, that could keep webmasters honest forever, otherwise you’ll have no idea when you will be punished.

Tim March 2, 2010 at 2:12 am

Hi Chris,

The whole idea of reverse trust is a theory put out many years back by Yahoo. I have not personally seen any penalties for say “not having a link for the yahoo directory” , however I have seen penalties from linking out to suspect spam sites. I work with a huge client who got completely deindexed for linking out to less than ethical websites.

I don’t think anyone knows how trust or reverse trust really works, the only thing I would advise is to be careful who you vouch for.

Val March 12, 2010 at 2:11 pm

I just purchased a couple of expired domains at auction that have PR2. Do you know what the best way to point them to my optimized domain so as to pass their trust and pagerank to the optimized domain?

Tim March 15, 2010 at 1:56 am

Hi Val,

If you bought the domain for it’s link profile then you should 301 the domain using the ht.access. Don’t do this with too many different domains as Google can class it as spamming if you buy loads of domains.

Erik November 14, 2010 at 6:26 pm

Say a PR page 7 links to a Pr 0 , does that PR 7 page loses its PR and sends 7 to the Pr 0 ( assuming one link on the page )? Is there a way for it to lose its PR? or does it pass made up PR. Like the page keeps PR and still passes? What’s the deal with that.

Tim November 15, 2010 at 2:11 am

Hi Erik,

PR cannot be lost, there is a value passed on to the site being linked to but the site sending the link is safe. If Google thinks you are selling links that is completely different matter and your PR can be removed because of it.

Mags January 3, 2011 at 10:44 am

It’s a really interesting article. I always explain that to my clients, link doesn’t have to point from page with high PR, but the domain trust is crucial. I am a big fan of article marketing. Just to remind: the first commandment of seo says: Content is a King:)

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