Spam Score Explained: What Moz's Spam Score Means and When to Worry

Spam Score causes more unnecessary panic than almost any other SEO metric. Someone checks their site in Moz, sees 18%, and assumes Google thinks they're spammers. That's not what the number says, and once you understand what it does say, it becomes a handy screening tool rather than a source of worry.

What Spam Score actually measures

Spam Score is a Moz metric expressed as a percentage. Moz looked at large numbers of sites that had been penalized or removed from Google's results and identified features those sites tended to share. When Moz calculates a Spam Score for a site, it's estimating what percentage of sites with similar features were penalized or banned.

So a Spam Score of 40% means roughly: among sites that look like this one on Moz's checklist of features, about 40% were found to be penalized or banned. It does not mean this particular site is 40% spam, and it doesn't mean Google has taken any action against it.

Moz groups scores into ranges:

• Low: 1% to 30%
• Medium: 31% to 60%
• High: 61% to 100%

What kind of signals feed it

Moz doesn't hand out a public weighting for every feature, but the signals are the sort of thing you'd expect from spam sites. Examples include a very small number of pages, thin content, little branded anchor text in the site's link profile, unusual top-level domains often associated with spam, a heavy ratio of links to content, and missing basics such as contact information or a clear site name.

Plenty of legitimate sites trip some of these. A brand new consultancy site for a CA firm in Pune might have six pages, no backlinks yet and a short About page. It could show a medium Spam Score simply because it looks like a thin site, which it currently is. That's not a penalty, and it will usually fall as the site grows.

Spam Score is a correlation, not a verdict

This is the point to hold on to. Spam Score tells you a site resembles spam sites on certain features. It doesn't tell you whether Google treats it as spam. Google doesn't use Moz's Spam Score and has its own systems, including SpamBrain, for detecting spam and link manipulation.

Treat Spam Score like a smoke alarm. When it goes off, look for fire. Sometimes it's just toast.

Using Spam Score to vet link prospects

Where Spam Score earns its keep is in screening sites before you get a link from them. If you're going through a list of 200 guest post prospects, sort by Spam Score and look closely at anything in the medium or high range.

For each flagged site, do a two-minute manual check:

1. Open the homepage and two recent articles. Is the content written for people or stuffed with outbound links?
2. Look at the outbound links. Are they all to casinos, loan sites and supplements in unrelated articles?
3. Check whether the site has organic traffic in any SEO tool, or whether it's a high-score shell.
4. Search site:domain.com in Google to see whether it's indexed properly.

A medium score plus thin, link-heavy content means walk away. A medium score on a small but genuine niche blog may be fine.

Using Spam Score on your own link profile

Moz's Link Explorer can show the Spam Score of the domains linking to you. Filtering your linking domains by high Spam Score is a fast way to build a shortlist for a backlink audit.

Shortlist is the right word. Don't take every high Spam Score domain and paste it into a disavow file. Many of those links are scrapers, directories and auto-generated pages that every site picks up, and Google is generally good at ignoring them. Disavowing in bulk based on a third-party score can throw away links that were actually helping. Our disavow tool guide explains when disavowing is worth it.

What should concern you is a pattern: lots of high-score domains linking with exact-match commercial anchors, especially if you or a past agency built them. That combination looks like a link scheme, and it's the kind of thing that leads to a manual action.

Why your own Spam Score might be high

If your site shows a medium or high Spam Score, check the obvious causes:

• Very few pages. Add genuinely useful content.
• Few or no backlinks, or mostly low-quality ones. Earn links from real sites in your field.
• Missing trust basics. Add a proper About page, contact details, a privacy policy and a clear brand name in the title tags.
• Unusual domain extension. Not much you can do here except build a strong site on it.

Then watch Search Console. If impressions and clicks are healthy and there's no manual action listed, Google isn't treating your site as spam, whatever the score says.

Where Spam Score fits

Spam Score works best as one column in a vetting spreadsheet, next to domain authority, traffic estimates and a relevance check. On its own it creates false alarms and false comfort in roughly equal measure.

Your next step: export your linking domains from Moz, filter for Spam Score above 60%, and open the top 20 by hand. Note which ones look like ordinary web junk and which ones look like links someone deliberately built. Only the second group needs any further action.