Domain Authority is a score that predicts how well a website will rank in search results

Domain Authority (DA) is a number from 1 to 100 that estimates how likely a domain is to rank highly on Google. It's calculated by analyzing the quality and quantity of links pointing to a site. A higher score suggests the site has built more trust and authority over time, which search engines tend to reward with better rankings.

The score itself doesn't come from Google — it's created by Moz, a company that studies search engine behavior. Google doesn't publish its own authority metric, so Moz's version is the most widely used reference point in the industry. Understanding your own DA, or a competitor's, can show you where you stand relative to other sites in your field.

Domain Authority is different from Page Authority, which measures individual pages rather than entire domains. It's also separate from your actual search rankings, which depend on many other factors including content quality, user experience, and how well your pages match what people are searching for.

Key Takeaways

  • Domain Authority ranges from 1 to 100 and is based on the quantity and quality of links pointing to your site, not on Google's own ranking algorithm.
  • You can check DA for free using Moz's toolbar or by visiting moz.com/domain-analysis, or through paid SEO tools like Ahrefs, SEMrush, and Ubersuggest.
  • A higher DA usually correlates with better search rankings, but it's one signal among many — content quality and user experience matter just as much.
  • Your own DA changes slowly over time as you earn more backlinks; checking it monthly or quarterly is more useful than checking it daily.

Free tools to check Domain Authority

Moz offers a free Domain Authority checker at moz.com/domain-analysis. Enter any domain name and you'll see its DA score, along with Spam Score (a measure of how many low-quality links point to it) and a few other metrics. No account is required, and you can check as many domains as you want.

The Moz toolbar is another free option. Install it as a browser extension in Chrome or Firefox, and it displays DA for any site you visit. This is useful if you're researching competitors or evaluating link opportunities — you can see scores without leaving your browser.

MozBar, Moz's paid version of the toolbar, adds more detailed information like Page Authority for individual pages and keyword difficulty scores. The free version gives you enough to understand the basics.

Paid SEO tools that include Domain Authority

Ahrefs, SEMrush, and Ubersuggest all display Domain Authority alongside their own proprietary metrics. Ahrefs calls its version "Domain Rating" (DR), while SEMrush uses "Authority Score." These tools cost money — Ahrefs starts around $99 per month, SEMrush around $120, and Ubersuggest around $12 — but they offer far more than just DA.

If you're managing multiple sites or doing competitive analysis regularly, these tools are worth the investment because they show you where competitors' links come from, which keywords they rank for, and what content performs best. For occasional checking, the free Moz tool is sufficient.

Some tools update their scores more frequently than others. Moz updates roughly monthly, while Ahrefs and SEMrush may update more often. If you're tracking your own site's progress, consistency matters more than frequency — pick one tool and check it on the same schedule each month.

What Domain Authority actually measures

DA is built on the idea that links are votes of confidence. When another site links to yours, Moz treats that as a signal that your content is worth referencing. The algorithm weighs links differently based on the authority of the linking site — a link from a high-DA site counts more than a link from a low-DA site.

The quality of links matters more than the quantity. A single link from a relevant, high-authority site in your industry is worth far more than dozens of links from unrelated, low-quality sites. Moz's Spam Score tries to flag sites that have accumulated many low-quality links, which can actually hurt your rankings.

Domain Authority does not measure content quality, user experience, page speed, mobile-friendliness, or how well your site matches what people are searching for. Google considers all of these factors when ranking pages. A site with high DA but poor content will still struggle to rank if the content doesn't answer what searchers want.

Why Domain Authority matters, and why it doesn't

DA correlates with search rankings — sites with higher DA tend to rank better. This makes it a useful shorthand for understanding a site's overall authority. If you're trying to decide whether to pursue a link from another site, checking their DA gives you a quick sense of whether that link will help you.

However, DA is not a ranking factor itself. Google doesn't use Moz's score in its algorithm. A site with DA 40 can outrank a site with DA 60 if the lower-DA site has better content, better user experience, or better keyword targeting. Focusing only on DA and ignoring content quality is a common mistake.

For your own site, DA is most useful as a long-term trend indicator. If your DA is rising over months, it usually means you're earning quality backlinks and building authority. If it's flat or declining, it might signal that your link-building strategy needs adjustment or that you're losing links you previously had.

How to improve your Domain Authority

The primary way to raise DA is to earn backlinks from other sites, especially high-authority sites in your industry. This happens naturally when you create content worth linking to — research, original data, tools, or guides that other sites want to reference. It's slow but sustainable.

You can also pursue links more actively by reaching out to relevant sites, asking if they'd link to your content, or finding broken links on other sites and suggesting your content as a replacement. This requires time and relationship-building, but it's more reliable than waiting for links to appear on their own.

Avoid link-buying schemes or link farms. These tactics may temporarily boost your link count, but Google penalizes sites with unnatural link patterns, which can tank your rankings. Moz's Spam Score will flag these kinds of links, and they'll hurt more than they help.

Domain Authority vs. other authority metrics

Ahrefs' Domain Rating (DR) and SEMrush's Authority Score are built on similar principles to DA — they measure backlink quality and quantity — but they use different algorithms and update on different schedules. If you check the same site across all three tools, the scores may differ by a few points.

Google's own metrics, like Core Web Vitals and PageRank (which Google no longer publicly shares), measure different things. Core Web Vitals focus on user experience — how fast pages load, how stable the layout is, and how responsive the site is to input. PageRank, Google's original algorithm, measured link authority but in a way Google kept private.

For practical purposes, any of these tools — Moz, Ahrefs, or SEMrush — will give you a reasonable picture of a site's authority. Pick one and stick with it so you can track trends over time. Switching between tools makes comparison harder because the scores won't align.

Frequently Asked Questions

How often should I check my Domain Authority?

Monthly or quarterly is typical. DA changes slowly as you earn new backlinks, so checking more frequently won't show meaningful change. Checking too often can create false impressions that your strategy isn't working when the score simply hasn't updated yet.

Is a Domain Authority of 30 good?

It depends on your industry and how long your site has existed. A new site with DA 30 is doing well; an established site with DA 30 may be underperforming. Compare your DA to direct competitors to see where you stand relative to them.

Can I check Domain Authority for a competitor's site?

Yes. Enter their domain into Moz's free checker or any paid SEO tool. This shows you their DA, where their backlinks come from, and which pages rank best. This research can inform your own link-building and content strategy.

Does Domain Authority affect my Google rankings directly?

No. DA is Moz's estimate of authority, not a Google ranking factor. However, the underlying signal — quality backlinks — does affect rankings. High DA usually correlates with good rankings, but the correlation isn't perfect.

What's a realistic Domain Authority for a new website?

New sites typically start at DA 1 or not measurable at all. Reaching DA 10 to 20 within the first year is reasonable if you're earning quality backlinks. Reaching DA 30 or higher usually takes several years of consistent link-building and content creation.