Spam Score
Spam Score is a Moz metric, shown as a percentage, that estimates how likely a domain is to be penalized or low quality based on patterns seen in penalized sites.
Spam Score was created by Moz to flag risky domains. It works by checking a page or domain against a list of features (such as thin content, unusual link patterns, or a missing contact page) that statistically correlate with sites Google has penalized. A higher percentage means more of those red flags are present.
It is a fast triage tool when you are vetting referring domain prospects or auditing your own profile for a disavow decision. A domain with a very high Spam Score deserves a closer manual look before you accept a link from it or build one to it.
The important caveat is that Spam Score is correlational, not causal. A high score does not prove a site is harmful, and a low score does not guarantee safety. Plenty of legitimate sites score moderately, and some spam sites score low. Always pair the number with a human review of the content, the link, and the surrounding neighborhood rather than disavowing on the metric alone.