seo

Linkscape's Metrics

Linkscape computes a number of link-based metrics similar to those used by search engines for ranking. These metrics relate to both pages and domains, and measure several views of global authority or popularity, trust, spam, and freshness of data.

Internal and External Link Counts

Linkscape counts the number of links in its index for any given page. This overall total includes juice-passing and non-juice-passing links (e.g., rel=nofollow). To give you a better view on the links that matter the most, juice-passing links are broken down into internal and external and the amount of juice each contributes to any given page is calculated. When added together, the number of internal and external links equal the number of juice-passing links, which will be less than the total number of links to any given page.

mozRank (mR)

mozRank refers to both SEOmoz's general, logarithmically scaled 10-point measure of global link authority or popularity as well as an algorithm for computing that measure. mozRank is very similar in purpose to the measures of static importance (meaning independent of a specific query) used by the search engines (e.g., GOOGLE's PageRank¹ or FAST/AlltheWeb's StaticRank). Search engines often rank pages with higher global link authority ahead of pages with lower authority. Because measures like mozRank are global and static, this ranking power applies to a broad range of search queries, rather than pages optimized specifically for a few keywords.

The intuition behind mozRank is to leverage the democratic nature of the web. Every page has a vote. Pages can cast that vote by linking out to other pages, although their vote then becomes diluted with more links; thus, pages which link to many other pages aren't able to overwhelm those which only link to a few other pages. The idea is that you have a single amount of votes to cast, which you can cast all in one link or a little bit over many links. Each link is considered an endorsement. Highly endorsed pages are both considered more authoritative as well as able to more authoritatively endorse pages they link to.

External mozRank

External mozRank measures the amount of mozRank flowing through a link located on a separate domain. Because external links can play an important role as independent endorsement, external mozRank measures an important factor for ranking.

Domain-Level mozRank (DmR)

Domain-level mozRank describes, on its own logarithmic 10-point scale, where your domain stands amongst all other domains. DmR is computed for both subdomains and root domains, and are not directly comparable. DmR uses the same mozRank algorithm but applies it to the "domain-level link graph." Doing so offers additional insight about the general authority of the domain. Just as pages can endorse other pages, a link which crosses domain boundaries (e.g., from some page on searchengineland.com to a page on www.seomoz.org) can be seen as endorsement by one domain for another.

Domain Juice (DJ)

Domain Juice is the sum of mozRanks for all URLs in a domain. It is shown on the same 10 point logarithmic scale that mozRank uses. Analyzing Domain Juice can help determine how much of the Internet's mozRank is on one domain compared with another.

Domain Juice is an aggregate view of the raw link juice controlled by all the URLs on your domain. Rather than DmR, which considers the best view of your domain and values domain diversity, Domain Juice considers the broader view of your domain at the page-level, considering your strongest and weakest links and your most and least popular URLs, even if they all come from just a few domains. Because of this, DmR and Domain Juice should not be directly compared. Instead, you should compare the DmR from one domain against the DmR from another and do the same with Domain Juice.

Domain Juice is reported on the same scale as mozRank, so you can see how important any given URL is to the domain it's on by comparing URL-level mozRank with domain juice. Because of this, Domain Juice may exceed the 10-point mozRank scale if a domain has many high mozRank URLs. For example, any domain having two mozRank 10 URLs would immediately have a Domain Juice of more than 10.

External Domain Juice

External Domain Juice measures the amount of mozRank flowing into your domain from external sources. Similar to external mozRank, external domain juice measures an important ranking factor, but across an entire domain.

mozTrust (mT)

Just as links express global link popularity, they also express something about the trustworthiness of your URLs. Receiving links from sources which have inherent trust, such as the front pages of some universities or certain governmental pages, is a strong endorsement, not necessarily of popularity, but of trust. mozTrust is a quantitative measure of this trust.

Like with mozRank, trust-votes are distributed through links. First, trustworthy "seeds" are identified to start the process, rather than granting voting equality across the web. Those that earn trusted links are able to cast (smaller) trust-votes through their links. Receiving a trust-passing link from a highly trusted source boosts your own trust.

mozTrust is expressed on its own 10-point logarithmic scale. While mozRank and mozTrust should not be directly compared, it can be interesting to consider how these two values relate to each other across several URLs. A URL with a large mozRank-mozTrust disparity may perform more poorly against a lower mozRank URL but with a smaller mozRank-mozTrust disparity.

Domain-Level mozTrust (DmT)

Just as mozRank can be applied to domain-to-domain links, so can mozTrust. Domain-Level mozTrust considers the trust garnered by all site-level endorsements. New or poorly linked-to pages on highly trusted domains may inherit some natural trust by virtue of being hosted on the trusted domain. Domain-Level mozTrust is expressed on another 10-point logarithmic scale.

Crawl Freshness

The "crawl freshness" reported for a URL or domain reflects how up to date the information in Linkscape's index is, specifically information about links. Freshness takes into account the recency of a crawl of linking URLs as well as the importance of those links to a target URL or domain.

mozRank Passed and Domain Juice Passed

Every juice-passing link contributes to the target URL's mozRank (and therefore the target domain's Domain Juice). When considering the value of a link, it's important to consider not just attributes about the source of the link (like the source's mozRank, Domain Juice, mozTrust, etc.), but also how this link itself contributes to the target. One of the most interesting metrics Linkscape makes available is the mozRank passed (and the Domain Juice passed) by each link. This gives you a very concrete measure of the value of this link compared to all other links to a target URL or domain. The value is related to, but different from, the source's mozRank according to the mozRank algorithm.