Definition
Domain authority is a score, created by third-party SEO companies, that estimates how strong a whole website is likely to be in search results. It is usually a number, often on a scale up to 100, meant to predict how well a site can rank based on signals like the quality and number of other sites linking to it. A higher score suggests a more established, credible site. It is a useful rough gauge of a website's overall standing, but it is widely misunderstood.
Domain authority matters because it gives a quick sense of a site's strength and is handy for comparing sites, but it is important to understand what it is and is not. It is an outside estimate, not a score that search engines themselves use to rank pages. This page explains what domain authority is, how it works, why it is useful, the critical thing people get wrong about it, and how to actually build the authority it tries to measure.
What domain authority is
Domain authority is a third-party estimate of how strong a website is in search, expressed as a score. It is calculated by SEO companies, not by search engines, and it tries to predict a site's ranking strength based largely on the quality and number of sites that link to it.
Think of it as an outside credit score for a website. It is one company's educated estimate of how trustworthy and established a site is, useful as a rough gauge, but not an official judgment from the search engines themselves.
How domain authority is calculated
Domain authority is calculated mainly from a site's backlink profile, the quality and quantity of other sites that link to it, along with related signals. The more reputable sites that link to a website, the higher its estimated authority tends to be.
Because each SEO company calculates its own version, the exact number depends on who is measuring. The scores are most useful for comparison, seeing whether one site is stronger than another, or whether a site is trending up over time, rather than as an absolute, official figure.
Why domain authority is useful
Domain authority gives a fast, rough read on how established a website is, which is handy for comparing your site to competitors or judging whether a site is a strong place to be linked from. It packages a complex picture into a single, easy number.
It is also useful for tracking progress. Watching your estimated authority rise over time can confirm that your efforts to build a credible, well-linked site are working, even though the number itself is just an estimate.
Domain authority vs page authority
| Domain authority | Page authority | |
|---|---|---|
| What it estimates | The strength of a whole website | The strength of a single page |
| Scope | The entire domain | One specific page |
| Useful for | Comparing whole sites | Comparing individual pages |
| Both are | Third-party estimates, not official | Third-party estimates, not official |
The big thing people get wrong
The most important thing to understand is that domain authority is not a score search engines use to rank your pages. It is an outside estimate created by SEO companies, not an official ranking factor. Chasing the number as if search engines cared about it directly is a mistake.
Obsessing over the score also misses the point. Domain authority tries to measure something real, a site's genuine credibility and standing, so the goal should be building that underlying strength, not gaming a third-party number. Improve the real thing, and the estimate tends to follow.
How to actually build authority
- Treat domain authority as a rough gauge, not an official ranking factor.
- Use it for comparison and tracking trends, not as a target to game.
- Build genuine authority by publishing content worth linking to.
- Earn quality links from reputable, relevant sites over time.
- Focus on the real standing the score tries to estimate.
Building the real authority behind the score
Domain authority tries to measure a site's genuine credibility, and the way to raise it is to build that credibility for real, by publishing content so useful that reputable sites link to it. There is no shortcut around being worth linking to.
Infrasity focuses on creating that kind of link-worthy technical content, which builds real authority over time. Improve the underlying strength of a site, and the score that estimates it tends to rise on its own.
Frequently asked questions
What is domain authority?
It is a score created by third-party SEO companies that estimates how strong a whole website is likely to be in search, based largely on the quality and number of sites linking to it. A higher score suggests a more established, credible site. It is a rough gauge, not an official measure.
Does Google use domain authority to rank pages?
No. Domain authority is an estimate made by outside SEO companies, not a score search engines use to rank your pages. It tries to predict ranking strength, but chasing it as if it were an official ranking factor is a common mistake.
What is the difference between domain authority and page authority?
Domain authority estimates the strength of a whole website, while page authority estimates the strength of a single page. Both are third-party estimates rather than official figures. Domain authority is useful for comparing sites, page authority for comparing individual pages.
Related terms
Backlinks, Search Engine Optimization (SEO), Organic Traffic, Content Cluster, Dwell Time