Page Authority is a score (on a 100-point scale) developed by Moz that predicts how well a specific page will rank on search engines. It is based off data from the Mozscape web index and includes link counts, MozRank, MozTrust, and dozens of other factors. It uses a machine learning model to predictively find an algorithm that best correlates with rankings across the thousands of search results that we predict against.
The amount of link juice passed depends on two things: the number of PageRank points of the web page housing the link, and the total number of links on the web page 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, web pages on the most powerful and significant websites can pass link juice points in the hundreds or thousands.
Domain Authority is a score (on a 100-point scale) developed by Moz that predicts how well a website will rank on search engines. Use Domain Authority when comparing one site to another or tracking the “strength” of your website over time. We calculate this metric by combining all of our other link metrics—linking root domains, number of total links, MozRank, MozTrust, etc.—into a single score.