Domain Authority (DA) is a score that shows how a website ranks on search engine result pages (SERPs).
The score, developed by Moz, is expressed with a number between 0 and 100. The higher the score the better the website ranks on searchability.
Sites like Google.com have a large number of external links and are therefore at the top for the Domain Authority global ranking.
What is a good Domain Authority score?
The DA score depends on the number and the quality of domains linking to your site. The more links to your site, especially from relevant and popular sites, the higher your site's domain authority will be. And, of course, this number is dynamic and often changing.
A good score will be above 50, whilst a great score will usually be above 70. According to DA specialists, it is much easier to increase the score from 0 to 20 than to improve it when it is already above 70.
How can you check your Domain Authority?
You can check the domain authority of your site using some free SEO tools including MozBar. This is a good place to start to see what your DA score is and how you can start improving it.
To find out more technical information on Domain Authority you can visit Moz here.