Spam Score

Spam Score is a metric from the SEO tool Moz that estimates how likely a website is to be penalised or banned by Google, based on features it shares with known spam sites. It is shown as a percentage and helps you judge backlinks and link prospects, but it is not a Google metric.

Written by Paul Hoda, SEO consultant since 2005. Last updated 8 November 2026.

How Spam Score works

Moz studied large numbers of sites that had been penalised or removed from Google’s results and identified features they had in common. Spam Score represents the percentage of sites with similar features that Moz found to be penalised or banned. So a score of 60% does not mean a site is 60% spammy: it means that, among sites that look similar, around 60% had problems.

The features are signals such as thin content, very low numbers of pages, unusual link patterns or missing basic site information. No single feature makes a site spam. The score reflects a combination.

Because it is based on patterns, Spam Score describes risk rather than intent. It cannot tell whether a site owner is deliberately spamming, simply inexperienced, or running a small site that happens to share some features with spam.

Reading the score

  • Low: the site shares few features with penalised sites.
  • Medium: worth a closer look, especially if you are considering a link from it.
  • High: a strong prompt to investigate before trusting the site.

Moz calculates Spam Score for domains and subdomains, and you can view it alongside Domain Authority in its tools.

Why it matters for SEO

Spam Score is a quick filter during backlink analysis and when vetting link prospects. It helps you spot domains that may be part of private blog networks, link farms or abandoned spam sites.

It should not be the deciding factor. Google does not use Moz’s Spam Score, and Google has said its systems are generally good at ignoring spammy links. Many perfectly fine small sites score higher than you might expect simply because they are small or new.

How to use it sensibly

  1. Export your referring domains with their Spam Scores.
  2. Sort by score and review the highest manually.
  3. Visit each site: check content quality, real purpose, outbound links and whether it has genuine visitors.
  4. Only consider removal requests or the disavow tool for links that are clearly manipulative, especially if you have a manual action.
  5. For prospects, use Spam Score with relevance and traffic checks before outreach.

Common mistakes

  • Disavowing every link with a high score, which can throw away harmless or useful links.
  • Assuming a low score means a site is high quality.
  • Treating the number as a Google penalty indicator rather than a statistical estimate.
  • Panicking about toxic backlinks based on tool scores alone, without reviewing the sites themselves.

Key Takeaways

  • Spam Score is a Moz metric shown as a percentage.
  • It reflects how often similar sites were penalised or banned by Google.
  • A high score means investigate, not automatically disavow.
  • Google does not use Moz’s Spam Score.
  • Small and new sites can score higher without being spam.
  • Always review suspicious sites manually before acting.

Related Terms

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