Not All Links are Created Equal

  • Links are links, right? Wrong. Every inbound link you have coming to your site has a different level of trust and respect from Google.
  • Not only is Google repeatedly analysing your site and indexing it for keyword phrases and valuable content, but it’s doing the same thing for all the sites that link to you.
  • When doing so, if Google finds that a site that links to you is reputable, then the link is valued more highly.
  • If the link is from a low quality, or spammy source, then the link will be devalued, or carry no weight (juice) at all.
  • So the quantity of links to your website is important to know as we can spot any sudden increases and decreases and attend to the problem.
  • But still, just one very high value link from a popular website, can carry more value and offer you more benefits than tens or even hundreds of links from lower quality websites.

SEO KPI Definitions

  • External Backlinks (Majestic SEO): The total number of backlinks pointing to your website as determined from MajesticSEO’s Historic Index. This is a historic database of billions of link records, and it can increase and decrease from gaining and losing links, and also when MajesticSEO chooses to update or refresh their index (their ‘snapshot’ of the internet).
  • External Backlinks (Moz): The total number of backlinks pointing to your website as determined from Moz’s  Site Explorer tool.
  • Citation Flow: Citation Flow is a Flow Metric from Majestic SEO, which weights your website by the number of times a given URL or domain is cited (or linked to) by external pages.
  • Trust Flow: Trust Flow is a Flow Metric from Majestic SEO, which predicts trustworthiness based on how trusted the external websites linking to you are.
  • Domain Authority: Domain Authority represents Moz’s best prediction about how a website will perform in search engine rankings. This prediction is calculated by combining all other Moz link metrics (linking root domains, number of total links, mozRank, mozTrust and more) into a single score.
  • mozRank: MozRank represents a link popularity score and reflects the importance of any given web page on the internet. Pages earn MozRank by the number and quality of other pages that link to them; the higher the quality of the incoming links, the higher the MozRank.
  • mozTrust: MozTrust is Moz’s global link trust score. It is similar to MozRank but, rather than measuring link popularity, it measures link trust. Receiving links from sources which have inherent trust, such as the homepages of major university websites or certain governmental web pages, is a strong trust endorsement.


Page Rank (PR)

Calculated by: GoogleScale: 0 – 10 (integer numbers)

Formula: PR indicates a webpage’s popularity across the web. This means that it only takes into account how many links are pointing to a page, regardless of their quality or anchor text details.Also, most important you must keep in mind that PR can only be calculated for a webpage and NOT for a website.Although Google updates PR calculus for webpages often and very often (we’re talking about hours) those values are not available to us. Google makes PR public through the PR Toolbar which is only updated once in a 3 to 9 months period.The PR toolbar is available for free and you can find the instructions on how to enable it on this page.

Analysis: Although it’s the most popular SEO metric, PR is no longer a determining ranking factor, neither a relevant metric for SEO analysis. PR is only one of the 200 signals Google looks at when determining websites’ position in search results and a rough meter for a webpage’s inbound links.You can efficiently use it to compare the link profile of different pages and to spot eventual penalties from Google, but you must keep in mind that a drop in your PR can be due to other reasons, than a penalty or removed links.You PR fluctuates according to all the other pages on the internet because of the way PR is calculated. At first it is determined what it takes to be a PR 10 and from there all the other PRs are set. So, if the webpage with the most links across the internet has a PR 10 and increases even more its number of links, you might see a fall in your PR without having any changes in your link profile.

MozRank (mR)

Calculated by: SEOmozScale: 0 – 10 (two decimal numbers)

Formula: mR is meant to mimic Google’s PR. Therefore it only evaluates a page’s link profile taking into consideration the number of links.There are though a few differences between mR and PR:sometimes, when a website is caught to be performing bad seo practices, it gets penalized by Google through a PR drop. This punishment won’t be reflected in mR and thus differences will appear.mR is calculated as a decimal value to better represent a page’s performance while PR has integer values.SEOmoz has its own index of the web (Linkscape) based on which it calculates a set of seo metrics: mozRank, mozTrust, Domain mozRank, Domain mozTrust, Page Authority and Domain Authority. SEOmoz refreshes its link database about once per month, when these metrics are also re-calculated and updated.SEOmoz provides free access to mozRank, to PA and DA through its mozBar, while mozTrust, Domain mozRank and Domain mozTrust are available only to paying members of their community.

Analysis: Just like PR, mR is calculated logarithmically. This means that the distance between two consecutive mR points progressively increases. The number of built links that took you from a 2 mR to 3 mR, won’t be enough to take you from a 7 mR to 8 mR. The higher the mR, the tougher will be to make progress.This is where the two decimal points of mR come in hand. You can get a more accurate image of your position and better monitor your progress.

MozTrust (mT)

Scale: 0 – 10 (two decimal numbers)

Formula: mT sums up for a webpage the trust of its referrers determining thus its own trustworthiness. It’s important to be mentioned that not all of your built links are able to pass through trust. Only authoritative websites (.edu, .gov, .edu and well established websites) are counted for determining mT.

Calculated by: SEOmoz

Analysis: Comparing to mR which counts links and improves along with their number, mT is a metric that focuses more on quality rather than quantity. The latter should give you a sense of your page’s long term built strength.You can use it as a raw number or you can compare it to mR. The rate between mR and mT shows you the overall quality of your link profile and helps you understand what you should do to improve your performance.

Domain level mozRank & mozTrust (DmR/DmT)

Scale: 0 – 10 (two decimal numbers)Calculated by: SEOmozFormula: These are mR and mT calculated not for a webpage, but for the entire domain.As many SEOs do, you must not mistake the domain wide metrics with the metrics of your Index page. Although it is the most powerful page of your website, the Index page does not reflect the performance of your entire domain.Analysis:Domain wide metrics are extremely useful for evaluating your potential partners. For example, you should never judge a guest posting opportunity or a link building prospect by their page metrics. Instead, keep in mind that it’s far more effective to connect with low rank pages on strong and authoritative domains rather than seeking higher rank pages on less powerful domains.

Page Authority (PA)

Scale: 0 – 100 (integer numbers)

Calculated by: SEOmozSEOmoz uses a machine learning algorithm to determine correlations between link metrics and high rankings, aggregating them into the PA score.Formula: PA is meant to aggregate all the other SEO metrics into one and to reflect how prone/promising a page is for high rankings, considering only its link profile.Just like a fit person will probably perform any sport better that a non-active person, webpages with higher PA are more likely to achieve high rankings than pages with low PA.

Analysis: By comparing PA for the top 10 competitors on a specific search query, you will notice that PA is not fully correlated with rankings. This means that pages with lower PA may rank better than other more authoritative pages due to all the others factors Google is taking into consideration other than link metrics.However, PA is still the best rough indicator of a page’s stand alone performance in terms of optimization.

Domain Authority (DA)

Scale: 0 – 100 (integer numbers)

Calculated by: SEOmoz

Formula: DA is PA calculated for the entire domain.

Analysis: Unlike PA which is only relevant for optimization purposes, DA is a great metric for competitive analysis and partner selection.