What the score is and is not
Moz built Domain Authority from link data, such as how many separate websites link to a domain. Moz itself states that DA "is not a Google ranking factor and has no effect on the SERPs", and Google’s John Mueller has said several times that Google does not use it (Search Engine Journal).
Other SEO tools publish similar scores under their own names. Each company calculates its score from its own link data, so the same site can score very differently from one tool to the next.
How to use it sensibly
- Compare your site with competitors in the same tool, never across tools.
- Use it to judge whether a site is worth approaching for a link, alongside relevance.
- Never buy links because a seller promises a high DA.
Clients sometimes ask a freelancer to "raise our DA". The honest answer is that a better score follows better links and content. Raising the number on its own does nothing for rankings, traffic or sales.