What is domain authority, and does Google use it?
Short answer
Domain authority is a score that SEO software companies calculate to estimate how strong a website's backlinks are. No, Google doesn't use it. Google has said so publicly more than once. The score can be a rough way to compare two sites, but raising it isn't the same as ranking better.
Google doesn’t use domain authority, which is a score that SEO software companies calculate to estimate how strong a website’s backlinks are. Several vendors publish their own version under slightly different names, usually on a scale that runs up to 100. It’s a third-party estimate, not a Google measurement, and it doesn’t appear anywhere in Google’s own tools.
What the score measures
Each software company crawls as much of the web as it can, counts which sites link to yours, judges how strong those sites look, and reduces the result to one number. That number is the vendor’s view of your links.
Because each vendor crawls a different slice of the web and uses a different formula, the same website gets different scores in different tools. The number is also built from links alone, so it says nothing about whether your pages answer a customer’s question or whether the site loads on a phone. How good your reviews are doesn’t enter into it either.
Does Google use it
No. People who speak for Google’s search team have said so publicly, more than once, about these third-party scores.
Google does use links as one of many ranking signals, and it has its own ways of weighing them, which it doesn’t publish. Years ago Google showed a public link score in a browser toolbar. It retired that, and nothing public has replaced it. So a domain authority score is an outside estimate of something Google works out privately, by a method the vendor can’t see.
What the score is good for, and what it isn’t
Treat it as a rough comparison and never as a target.
| Reasonable use | Poor use |
|---|---|
| Comparing your links with a competitor’s, in the same tool, to see whether the gap is small or large | Setting a score as the goal of an SEO campaign |
| A first glance at whether a website is established or was built last month | Judging what a single link is worth by the score alone |
| Watching the direction over a long period | Reporting small monthly movements as progress |
Why chasing the number goes wrong
The score can go up while nothing improves in Google. That’s the weakness link sellers trade on. Links are priced by the score of the site they sit on, and whole networks of sites exist to show a high number and sell space. Buying those links breaks Google’s spam policies, and buying backlinks carries that risk whatever the score says.
The reverse also happens. A mention on a Chula Vista neighborhood association’s website or a trade supplier’s installer list may carry a low score in every tool. For a hypothetical HVAC company in the South Bay, it’s still a real link from a real local organization, read by people who might call. Sorting link opportunities by score alone would throw it away.
What to watch instead
The numbers worth your attention come from Google itself or from your own phone:
- Where you rank for the searches your customers make, measured across your service area and not from one desk.
- Clicks and impressions in Google Search Console, which come from Google itself.
- Calls and form submissions that started with a search.
If a monthly report leads with a domain authority figure, ask what happened to those three over the same period. There are other numbers worth asking about when you read an SEO report.
Links do matter for organic SEO, and I do link building for clients. The score is at most a footnote in that work. I judge a link by whether a real organization with a reason to mention the business would publish it, and I measure rankings before and after.