Site Authority Checker

Type any domain into a site authority checker and you get a score that estimates how strong the whole website is in search. But "site authority" means slightly different things in every tool, and none of them come from Google. This guide decodes what each metric measures, which free checkers to use, and how to actually strengthen a site rather than chase a number.

What "site authority" really means

Site authority is a convenient phrase for a family of predictive scores that SEO companies built to answer one question: how likely is this whole website to rank? Because there is no official Google number, each vendor invented its own. Moz has Domain Authority, Ahrefs has Domain Rating, Semrush has Authority Score, and Majestic has Trust Flow. When someone says "check my site authority," they usually mean run the domain through one of these tools and read the resulting figure, typically on a 1 to 100 scale.

It is worth being precise about this, because vague authority talk causes bad decisions. Google's representatives have said many times that Google does not use a site-wide authority metric to rank pages, a point summarised well in Search Engine Journal's coverage of the subject. Google does evaluate broader quality signals, but it does not read Moz or Ahrefs scores. So a site authority checker measures a vendor's model of you, not Google's opinion of you.

Domain level versus page level authority

Most tools publish two numbers, and confusing them leads to wasted effort:

• Domain or site level scores estimate the strength of the entire website. Moz calls this Domain Authority, Ahrefs calls it Domain Rating.
• Page level scores estimate the strength of a single URL. Moz calls this Page Authority, Ahrefs calls it URL Rating.

A big site can have a high domain score while a specific thin page scores low, and that page will struggle to rank no matter how strong the domain is. Use the domain figure for benchmarking and the page figure to decide which individual URLs need more links or better content. If you want to focus on the whole-domain number specifically, our companion guide to the domain authority checker goes deeper on that metric.

Why every checker gives a different number

Run one domain through three tools and you will get three answers, sometimes far apart. That is not a bug. Each score comes from a different web crawl, a different index of known links, and a different weighting formula. Ahrefs might see backlinks that Moz has not crawled yet, and each company decides for itself how much a given link is worth. The scales are also all logarithmic, so moving up gets harder the higher you climb.

The practical rule is to pick one tool as your reference and stick with it. A rising trend inside a single tool is meaningful. A comparison of Moz's 42 against Ahrefs' 35 is not, because they are measuring different things on different scales.

Free site authority checkers worth using

404Pulse has no secret authority formula, and neither does any honest site. Use the free tools from the companies that actually built these metrics:

• Ahrefs Website Authority Checker returns Domain Rating for any domain with no signup.
• Moz Link Explorer reports Domain Authority and Page Authority with a monthly free query allowance after you register.
• Semrush shows an Authority Score in its free plan and browser extension.
• Google Search Console does not give an authority number, but it is the only free source that shows how Google itself crawls, indexes and ranks your pages, which matters more than any estimate. Google describes it as a free service to monitor and troubleshoot your search presence in its official overview.

If you specifically use Moz, our review of the Moz DA checker compares its free tier against the alternatives so you can pick the right one.

How to genuinely raise site authority

Because every authority score is driven mostly by links and content, the way to raise it is to improve those inputs. Chasing the number directly never works, but strengthening the fundamentals moves it reliably over time.

• Earn relevant links. A handful of links from respected, on-topic sites outweighs hundreds of low quality ones. Our link building guide lays out ethical tactics.
• Build topical depth. Cover your subject thoroughly with interlinked articles so both readers and search engines see genuine expertise.
• Audit your backlink profile. Use a backlinks checker to find and reclaim lost links and to spot toxic ones.
• Keep the site technically clean. Fix broken pages, redirect moved URLs, and pass Core Web Vitals so the strength you build is not leaking away.

Fixing the technical leaks that suppress authority

Even a well-linked site underperforms if authority drains through broken plumbing. Dead pages are the classic leak. When a linked URL returns a 404, the value of that link evaporates, so restore or redirect the page. When a URL returns a 404 Not Found response, as documented by MDN, any links pointing to it stop passing value, so redirect or restore it. Slow, unstable pages hurt too, because they degrade the experience Google measures through Core Web Vitals. Run key pages through PageSpeed Insights, aim to pass the thresholds defined by web.dev, and treat any failing metric as a priority fix. Together these repairs make sure the links and content you invest in actually compound. For the full workflow, see our guide to fixing broken links.

Frequently asked questions

What is a site authority checker?

It is a tool that estimates how strong a whole website is in search, usually on a 1 to 100 scale. Popular examples report Moz Domain Authority, Ahrefs Domain Rating or Semrush Authority Score. Each is a third party prediction, not an official Google metric.

Does Google use a site authority score?

No. Google has stated it does not use any site-wide authority metric from tools like Moz or Ahrefs to rank pages. Google evaluates broader quality signals, but it does not read these vendor scores, so treat them as benchmarking estimates rather than ranking factors.

What counts as a good site authority score?

It depends entirely on your niche and the tool you use. New sites often score in the single digits or teens, established sites commonly land between 30 and 60, and major brands reach the 80s and 90s. Compare yourself with direct competitors rather than aiming at a fixed number.

Why does my site score differently in each tool?

Every tool has its own crawl of the web and its own formula for weighting links, so their scores rarely agree. Choose one tool as your reference and track its trend over time instead of comparing numbers across tools.

Can I check site authority for free?

Yes. Ahrefs, Moz and Semrush all offer free authority checks with usage limits, and Google Search Console shows for free how Google actually crawls and ranks your site. Together they let you measure and improve your site without paying.