Domain Authority is a score developed by moz that predicts how well a website will rank on search engines

Domain authority is measured based on three factors age, popularity and size, it is a score developed by MOZ that predicts how well will a website rank on search engines.

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.

Domain Authority is a metric that can be used to understand how Google’s Algorithms rank you based on your authority or credibility on the web.
Domain authority is measured in 0-100 scale.