If you have looked into guest posting, you have seen the pitch: a list of sites with Domain Authority, Page Authority and Spam Score, sorted so the good ones float to the top. Filter for Spam Score under 5, the reasoning goes, and you are safe.
You are not. Not because the metric is bad — it is a reasonable metric, honestly built — but because it is answering a question you are not asking.
What Spam Score is
Spam Score is Moz's model. It estimates the likelihood that a domain shares characteristics with sites Moz has observed being penalised or removed from search results. It is trained on patterns — the shape of a link profile, on-page signals, domain traits.
Two consequences follow directly, and both matter.
It is a similarity measure, not a verdict. A low score means "this site does not currently resemble sites we have seen fail". It does not mean Google approves of the site, has assessed it, or would count a link from it. There is no such endorsement available from any third-party tool, at any price.
It describes the domain, not your placement. This is the part that quietly undoes most link-building filters. A genuinely respectable publication with a clean score can still host a paid-links section, a sponsored-content programme with no disclosure, or a contributor pipeline that publishes anything sent to it. The link you get from that section is not made acceptable by the reputation of the masthead above it.
Google's site reputation abuse policy exists precisely because this happens — third-party content published on an established site, trading on that site's signals rather than its editorial standards.
The document that actually governs this
If you do one thing after reading this, read Google's spam policies page for web search, specifically the link spam section.
It names the practices directly. Buying or selling links that pass ranking signals. Excessive link exchanges. Large-scale article campaigns with keyword-rich anchor text. Using automated programs or services to create links to your site. Requiring a link as a term of service or agreement.
That last-but-one item is worth sitting with, because it is the one most SEO tooling brushes against: using automated programs or services to create links to your site is named as link spam. Not researching prospects. Not drafting a pitch. Creating links.
This is why our own off-page workflow stops where it does. It finds candidate publishers, retrieves the Spam Scores that are available, and prepares a pitch draft. A person sends it. A publisher's editor decides. There is no button that places a link, and adding one would put the tool on the wrong side of the policy above — which is a strange thing to sell to someone whose goal is for their site to do well in Google.
Be suspicious of any service that will not explain where its automation stops.
A review checklist that means something
Metrics narrow a list. A human decides. Here is what to actually look at, in the order we find useful.
Is it about your subject?
Relevance is the cheapest check and the most predictive. A link from a small, focused site whose readers would genuinely care about your topic is worth more than one from a large general site that will publish anything. If you cannot explain in one sentence why this publication's readers would want your article, stop here.
Does a person edit it?
Open the last ten published posts. You are looking for signs of a human with standards: a house style, a consistent level of quality, subjects that hang together, articles that were clearly commissioned rather than received.
The opposite pattern is unmistakable once you have seen it — unrelated topics side by side, casinos next to health supplements next to crypto, several posts a day, every one with an exact-match keyword link in the third paragraph. That is not a publication. It is a link inventory.
What do the outbound links look like?
Read a few articles and look at where they link. Natural editorial links are contextual, varied in anchor text, and often point to sources rather than commercial pages. A site where every guest article contains one keyword-rich link to a commercial page has a business model, and it is not publishing.
Is money involved, and is it disclosed?
If a site quotes a price for a post containing a followed link, that is buying links, whatever it is called on the invoice — "contribution fee", "editorial fee", "processing fee". The remedy is not to avoid paying; it is that a paid placement's links should be marked rel="sponsored" or rel="nofollow". A publisher who takes payment and refuses to mark the link is telling you exactly what they are selling.
Would you send a reader there?
The simplest test and the hardest to game. If you would be slightly embarrassed for a customer to see where your article ended up, no metric redeems it.
What a prospect list is and is not
A researched prospect is a candidate for an approach. It is not a backlink, and a tool that reports thirty prospects has not built thirty links — it has found thirty places you might write to. Most will not reply. That is the normal, healthy shape of outreach, and any tool or agency presenting prospect counts as results is inviting you to misread them.
Spam Score, used properly, removes obviously bad candidates from a long list quickly. That is a real contribution and a modest one. The judgement that follows is not automatable, which is precisely why it is worth your time.