Quick answer: Domain Authority (DA) is Moz’s score, Domain Rating (DR) is Ahrefs’ score and Authority Score (AS) is Semrush’s score. All three rate a website from 0 or 1 to 100, but each uses different data and a different formula. DA predicts ranking potential, DR measures backlink strength, and Authority Score blends links, traffic and spam signals. Never compare a number from one tool with a number from another.
A link seller promises “DA 60”. Your agency reports “DR 45”. Your SEO tool shows “Authority Score 38”. Same website, three numbers. Which one is right?
All of them, in their own tool. This guide explains what each metric measures, when to use which, and how to avoid the mistakes that cost people money.
Domain Authority vs Domain Rating vs Authority Score at a Glance
| Domain Authority (DA) | Domain Rating (DR) | Authority Score (AS) | |
|---|---|---|---|
| Made by | Moz | Ahrefs | Semrush |
| Scale | 1–100 | 0–100 | 0–100 |
| Main question it answers | How likely is this domain to rank? | How strong is this domain’s backlink profile? | How trustworthy and strong is this domain overall? |
| Main inputs | Links and linking domains, modeled against real rankings | Number and strength of unique linking domains | Link power, organic traffic and spam signals |
| Page-level version | Page Authority (PA) | URL Rating (UR) | Page Authority Score |
| Best used for | Quick ranking-potential benchmarks | Link building and link prospect quality | Spotting domains with inflated link numbers |
Want a free score right now? The PageForge website authority checker gives you an independent 0–100 authority score plus the backlink data behind it, with no signup.
What Is Domain Authority (DA)?
Domain Authority is the original website strength score, created by Moz. It predicts how likely a domain is to rank in search results compared with other domains. Moz builds it by looking at links and linking domains and training the model against real ranking data.
Good for: a fast sense of ranking potential.
Watch out for: it’s the most widely quoted metric, so it’s also the one link sellers most often inflate or misquote.
What Is Domain Rating (DR)?
Domain Rating is Ahrefs’ measure of how strong a website’s backlink profile is. It focuses on how many unique websites link to a domain and how strong those linking websites are themselves. It doesn’t look at traffic or content.
Good for: comparing link profiles and choosing link-building targets.
Watch out for: a site can have high DR from links alone and still get almost no search traffic.
What Is Authority Score (AS)?
Authority Score is Semrush’s domain quality metric. It combines link strength with organic search traffic and signals of unnatural linking. Because traffic is part of the formula, a site with lots of links but no real visitors scores lower than you’d expect.
Good for: spotting domains that look strong on links but don’t perform.
Watch out for: traffic estimates can swing, which moves the score even when links don’t change.
Why the Same Website Gets Different Scores
- Different link indexes. Each company runs its own crawler and sees a different slice of the web.
- Different formulas. DA models ranking likelihood, DR models link strength, AS adds traffic and spam signals.
- Different update schedules. A score can move because the tool refreshed its data, not because anything changed on your site.
That’s why a DA 40, DR 55 and AS 32 can all describe the same website.
Which Metric Should You Use?
| Situation | Use |
|---|---|
| You already pay for one of these tools | That tool’s metric, consistently |
| You don’t pay for any tool | A free domain authority checker for benchmarks |
| Choosing sites to get links from | DR plus referring domains and relevance |
| Buying a domain or guest post | Two metrics side by side, plus real traffic |
| Reporting to a client or boss | One metric, same tool, tracked monthly |
Does Google Use DA, DR or Authority Score?
No. None of these metrics is a Google ranking factor. Google has its own internal signals and has said it doesn’t use third-party authority scores. These metrics are useful because they estimate things Google does care about, especially links from trusted, relevant websites.
4 Costly Mistakes With Authority Metrics
- Comparing across tools. “My DR is higher than their DA” means nothing.
- Trusting a screenshot. Always check the domain yourself. Scores in sales pitches are often old or fake.
- Buying on score alone. A high DR with no traffic is a classic sign of a link farm.
- Chasing the number. Rankings, traffic and leads pay the bills. The score is only a signpost.
Frequently Asked Questions
Is Domain Rating the same as Domain Authority?
No. Domain Rating is Ahrefs’ backlink strength score. Domain Authority is Moz’s ranking-potential score. They’re related ideas but calculated differently.
Which is more accurate, DA or DR?
Neither is more accurate in general. They measure different things. DR is more focused on links, DA on ranking likelihood. Consistency matters more than which one you pick.
Can I check Domain Rating for free?
Ahrefs offers limited free lookups. For a free alternative with no signup, use the PageForge authority checker, which shows a comparable 0–100 score and referring-domain data.
What’s the difference between Authority Score and Domain Authority?
Authority Score from Semrush includes organic traffic and spam signals. Domain Authority from Moz is modeled mainly on links and ranking data.
What is a good score in each metric?
The same rule applies to all three: a good score is close to the sites ranking for your keywords. Read what is a good domain authority score for ranges and a 5-minute benchmark method.
How to Read a Link Seller’s Numbers
Most people meet these metrics for the first time in a sales message: “DA 55 site, niche edit, $180.” Here’s how to check the claim in three minutes.
- Run the domain yourself. Never trust a screenshot. Scores are easy to fake and easier to leave out of date.
- Compare score to referring domains. A high score with very few linking sites usually means the score was manufactured.
- Look at the site’s own topics. A “business blog” covering casinos, CBD and insurance in four languages is a link farm.
- Search the site’s name in Google. If nothing shows up, it isn’t a publication anyone reads.
- Ask where the traffic comes from. No answer, or “we don’t share that”, is an answer.
A link is worth buying when the site would have linked to you anyway on merit. Everything else is renting a number.
Which Metric Fits Which Job
| Job | Metric to lead with | What else to check |
|---|---|---|
| Deciding if a keyword is winnable | Any one score, applied to all competitors equally | Page-level strength of the ranking pages |
| Choosing link prospects | Domain Rating | Topical relevance and real traffic |
| Vetting a domain purchase | Authority Score | History and spam signals |
| Client reporting | Whichever you started with | Referring domains, month over month |
| Tracking your own progress | Referring domains | Score, quarterly |
Why Scores Move When Nothing Changed
- The tool recalculated. Each provider updates its index and sometimes its formula.
- The scale is relative. If other sites gained links and you didn’t, you drift down without losing anything.
- Old links dropped off. Sites close, pages get deleted, links get removed in redesigns.
- A big link was discounted. Providers devalue links they decide aren’t editorial.
None of these are emergencies. Look at the three-month line, not the week.
Pick One Metric and Start Tracking
The metric you choose matters far less than using it consistently. Check your website authority free, record the score and your top competitors’, and repeat monthly. For a step-by-step process, see how to check domain authority.
