Domain Authority (DA) is a score from the SEO tool Moz that predicts how likely a website is to rank, based mainly on the links pointing to it. It runs from 1 to 100. Like Ahrefs’ Domain Rating, it’s a third-party estimate, and Google doesn’t use it.
Moz itself says so. Its explanation of the metric states that Domain Authority is calculated from factors including linking root domains and total links, and that it’s not a metric used by Google in determining rankings and has no effect on search results. When a prospect asks why their DA is lower than a competitor’s, the honest first answer is that Google never sees the number.
Domain Authority compared with Domain Rating
| Domain Authority (DA) | Domain Rating (DR) | |
|---|---|---|
| Made by | Moz | Ahrefs |
| Scale | 1 to 100 | 0 to 100 |
| Built from | Links, plus Moz’s quality and spam signals | Links only |
| Data source | Moz’s own link index | Ahrefs’ own link index |
| Used by Google | No | No |
The same site will show different numbers in each tool, because each company crawls the web separately and weighs links in its own way. Compare like with like: DA against DA, DR against DR.
Moz rebuilt the metric in March 2019 as Domain Authority 2.0, adding its Spam Score and changing how link quality is weighted. Scores from before and after that change aren’t comparable.
What Google says
Google’s June 2026 guidance on third-party SEO tools says Google doesn’t evaluate or endorse third-party tools, and those tools have no access to its internal ranking data. That applies to DA as much as any other score.
When DA is useful
DA is a sorting tool. It helps you rank a long list of link prospects by likely strength, and it gives a rough sense of how your link profile compares with direct competitors. Neither use treats DA as an outcome. If your DA rises and your leads don’t, nothing has improved for the business.
Common mistakes
- Reporting DA to leadership as a measure of SEO success.
- Paying for links because a site’s DA is high, without checking its relevance or real traffic.
- Comparing a DA score from Moz with a DR score from Ahrefs.
- Expecting rankings to follow a DA increase. Google ranks pages for searches, not domains by score.
- Comparing scores from before and after Moz’s 2019 rebuild.
Related terms
Domain Rating · Backlink · B2B link building · E-E-A-T · Topical authority
