Authority Score
Estimates a website's overall SEO strength on a 0–100 scale by combining backlink quality, organic traffic, and spam signals into a single proprietary score.
If you have ever chased a high score only to see no rankings move, you already know the number is a rough guide, not a ranking factor.
Key points
- Score fluctuations are normal: treat changes over weeks, not days, as meaningful signals.
- Compare scores only within Semrush tools; they vary too much across vendors to be portable.
- A high score from irrelevant backlinks does little for rankings; topical fit matters more.
- Use the score to prioritise link prospects, but always check the actual backlink profile.
- Semrush may update its formula without notice, so past scores are not guaranteed to hold.
- Do not use a single score change to judge a campaign; watch the trend across months.
Two competitor sites, same niche, different stories
A gardening blog had an Authority Score of 42 and 800 monthly organic visits. A rival site, same niche, scored 38 yet pulled 3,200 visits. The second site had fewer backlinks but more relevant, topic-clustered content and a natural link profile. The score undervalued its real traffic and topical authority. The higher-scoring site was propped up by spammy directory links, which Semrush's spam signals had not yet fully penalised.
Three situations where this changes your decision
- Evaluating a link prospect A low Authority Score on a site that ranks well for your target keyword may still be a good link opportunity — check relevance over score.
- Benchmarking against competitors Compare scores for five competitor domains to spot outliers; a high score with thin traffic suggests spam signals have not been applied yet.
- Tracking link-building progress Watch the score trend over two or three months after a campaign. A single monthly rise could be data noise, not real gain.
Four ways it goes wrong
- Treating it as a Google metric Google does not use Authority Score. Relying on it as a ranking signal will mislead your strategy. Use Google Search Central guidance for real ranking factors.
- Comparing across tools directly Semrush's Authority Score, Ahrefs' Domain Rating, and Moz's Domain Authority all measure different things with different scales. They are not interchangeable.
- Chasing the number blindly A score of 70 from irrelevant, high-spam backlinks is worse than 40 from natural, topically aligned links. The number alone does not tell you which is which.
- Reacting to short-term shifts A drop of 3 points in one week could be a recrawl or data refresh, not a real decline. Watch the three-month moving average instead.
Three things to check before acting
- Your actual backlink profile Open the Backlinks Tool and review referring domains manually. Look for spam patterns like identical anchor text or high dofollow ratios.
- Organic traffic estimates Compare the score's traffic estimate with your own analytics. If they diverge wildly, the score may be using stale or partial data.
- The source of the score Check when Semrush last updated its formula; the calculation can shift, making older scores unreliable. Also note whether the domain authority checker you are using is Semrush or another tool, as page authority and domain rating Ahrefs use different inputs entirely.
Common questions
What is a good authority score?
There is no universal good; it depends on your niche. A score above 50 is strong for a small business site, but 80+ is typical for established media domains.
How to increase domain authority?
Earn relevant backlinks from trusted sites and publish helpful content that attracts natural links. The score will follow slowly — there are no shortcuts.
What is domain authority vs authority score?
Domain Authority is Moz's score; Authority Score is Semrush's. They use different algorithms, so compare within the same tool only.
Sources
- Semrush Authority Score Help Official documentation of the metric's inputs and usage
- Semrush New Authority Score Update Details on spam-resistance updates and formula changes
- Google Search Central Official Google guidance on ranking, not third-party scores