DR or domain rating is a metric used Ahrefs. The proprietary metric assesses the strength of the backlink profile of a website. The quality and size of backlinks are assessed in isolation, which is to say not in comparison with the profiles of other websites. The metric is a standalone assessment for a particular website. However, in the larger scheme of things, the metric of one website does get pitted against another. This is especially in case of search engine optimization.
Domain rating works on a scale of zero to hundred. This is the logarithmic scale. Websites start from zero and can get their domain rating improved with a stronger backlink profile. It is easier to get from zero to ten than it is to progress from seventy to seventy five. This is simply because of how the assessment and the rating work. The higher one scales, the harder it is to improve the profile further for a progression of even one point.
Domain rating from Ahrefs has an affect on its ranking as well. Many experts consider the two to be the same. Domain rating does reflect the rank and vice versa. There is a subtle difference between the two. Domain rating tells the story of a backlink profile. The rank assigned by Ahrefs does not necessarily show the true picture of the backlink profile. Websites ranked one after another may have largely different profiles and their strengths may vary too. It should be noted that the domain rating from Ahrefs has nothing to do with the search engine result pages of Google and other rankings such as one provided by Alexa. Those working on search engine optimization should use the domain rating of Ahrefs as a reference to chalk out their backlink strategy and also to assess if the tactics at play are working.