Glossary
What is Domain Authority (DA)?
Domain Authority (DA) is Moz's 1 to 100 score that predicts how likely a website is to rank in search results compared with other sites. It's calculated by a machine-learning model mainly from Moz's link data. Like Domain Rating, it's a third-party metric; Google doesn't use it.
How DA is calculated
Moz trains a model to predict which domains rank higher in Google, using signals from its link index such as the number of linking root domains and their quality. The output is a score from 1 to 100 on a logarithmic scale. Moz updates the model and index from time to time, so a site's DA can move without any change on the site.
DA vs DR
| Domain Authority | Domain Rating | |
|---|---|---|
| Company | Moz | Ahrefs |
| Scale | 1 to 100 | 0 to 100 |
| Measures | Predicted ranking potential | Backlink profile strength |
| Method | Machine-learning model | Link-based formula |
| Index | Moz Link Explorer | Ahrefs |
It's common for the same site to show DA 35 and DR 55, or the reverse. Neither is wrong; they measure different things on different data. Search Console shows that people search "DA vs DR" and "is domain authority and domain rating the same thing" often; our article on DR vs DA answers it in full.
What a good DA is
As with DR, compare against the sites ranking for your searches. A DA of 30 is strong in a small local niche and weak against national publishers.
Common mistake
Treating DA as a goal or buying links to raise it. DA follows real authority; raising it artificially doesn't raise rankings. Sellers who promise "DA 50 in 30 days" are usually selling links from sites built to inflate scores.
Example
A directory advertises "DA 62". Moz confirms it, Ahrefs shows DR 38, and the site gets 4,000 visits a month. The DA is real but says little about whether a listing there will bring customers.
FAQ
Does Google use Domain Authority?
No. Google has said it doesn't use third-party authority metrics like DA.
Why is my DA different from my DR?
Moz and Ahrefs crawl different parts of the web and use different formulas.
How do I check DA?
Moz's free Domain Analysis tool and Link Explorer show DA.
Can DA drop without me doing anything?
Yes. Model updates, lost links and other sites growing can all lower it.
What is a good DA for a new site?
New sites usually start in single digits or low teens. Compare yourself with sites ranking for your target searches, and watch the trend rather than the number.