Page Authority is a metric developed by Moz that predicts how well a specific webpage will rank on search engine results pages. It is measured on a scale from 1 to 100, with higher scores indicating a greater likelihood of ranking well. This score is influenced by various factors, including the quality and quantity of backlinks, content relevance, and overall user engagement. To calculate Page Authority, Moz uses machine learning algorithms that analyze numerous factors from a large dataset. While it is not a direct ranking factor used by search engines like Google, it serves as a useful tool for webmasters and SEO professionals to assess and improve their pages' potential performance in search results.