If your website has accumulated backlinks over time, some of them are probably hurting you — and you may not know it. Spam score is the metric that tells you how at-risk your site is from search engine penalties due to low-quality, manipulative, or toxic links in your backlink profile.
This guide covers everything you need: what spam score is and who measures it, how to check the spam score of your website using free tools, how to interpret your score, and exactly what to do if your score is high. It also covers the specific data fields, toxicity reasons, and backlink categories that SEO tools use to calculate this metric — so you understand what you are actually looking at, not just the number.
What Is Spam Score?
Spam score is a metric developed by Moz — not Google — that estimates the likelihood that a website will be penalised by search engines based on the characteristics of its backlink profile and on-page SEO best practices signals. It is expressed as a percentage from 0% to 100%, where a higher percentage means a greater resemblance to sites that Moz has observed being penalised or banned.
Moz developed spam score by analysing hundreds of thousands of websites that had been penalised or deindexed by Google, then identifying the patterns those sites had in common. These patterns became the 27 spam flags that underpin the metric. A site's spam score is essentially a count of how many of those 27 flags it triggers, weighted by how strongly each flag correlates with penalisation.
Important distinction: Spam score is a Moz metric, not a Google metric. Google does not use Moz's spam score in its ranking algorithm. However, a high spam score is a useful warning signal because the flags it measures — toxic backlinks, thin content, unnatural link patterns — are the same kinds of issues Google's algorithms penalise independently.
Spam score ranges and what they mean:
| Score Range | Risk Level | What It Means for Your Site |
|---|---|---|
| 1% – 30% | Low risk | 92.6% of websites fall here. Your link profile is relatively clean. Minor monitoring is sufficient. |
| 31% – 60% | Medium risk | 5.7% of websites fall here. Review your backlink profile. Identify and disavow any clearly toxic links. |
| 61% – 100% | High risk | 1.7% of websites fall here. Immediate action required. Conduct a full backlink audit and disavow toxic links. |
How to Check Spam Score of Your Website
There are two ways to check your website's spam score: using Moz's Link Explorer (the original and most authoritative source) and using third-party tools that pull Moz's API data. Here is the step-by-step process for each method.
Method 1: Using Moz Link Explorer (Most Accurate)
- Go to moz.com/link-explorer and create a free Moz account if you do not already have one. The free plan allows 10 queries per month.
- Enter your website's domain URL in the search bar and click Analyse.
- Navigate to the Spam Score tab in the left sidebar of the results dashboard. You will see your overall spam score percentage alongside a breakdown of which spam flags your site is triggering.
- Review the 'Spam Flags' section to understand which specific signals are contributing to your score. Each flag tells you something specific — for example, a flag for 'few links to site' means your domain has low inbound link authority relative to its size.
- Export your backlink data using the 'Export' button to get a full list of links pointing to your site, with the spam score of each linking domain. This becomes your working document for backlink cleanup.
Method 2: Using Free Bulk Spam Score Checkers
If you want a quick check without setting up a Moz account, these free tools pull Moz data and display your spam score instantly:
| Tool | How Many URLs | How to Use It |
|---|---|---|
| smallseotools.com/spam-score-checker/ | Bulk (multiple at once) | Paste your URL, click Check. Displays spam score, DA, and PA instantly. No sign-up required. |
| dapachecker.org/spam-score-checker | Up to 5 URLs at once | Paste URLs (one per line), click Check Spam. Results show spam score alongside DA and PA. |
| websiteseochecker.com/spam-score-checker/ | Single URL | Enter URL, click Check. Displays Moz spam score with backlink overview. |
| linkody.com/en/seo-tools/website-spam-score-checker | Single URL | Enter domain. Shows spam score alongside backlink profile summary. |
Method 3: Using Moz Pro, Ahrefs, or SEMrush (For Agencies & Advanced Users)
For clients or sites requiring regular monitoring, paid SEO tools offer deeper spam score analysis:
- Moz Pro Link Explorer: the most comprehensive spam score data available, with full 27-flag breakdown, historical spam score tracking, and competitor comparison. Paid plans from $99/month.
- Ahrefs: uses its own 'Domain Rating' and toxic backlink detection, not Moz's spam score specifically. The 'Referring Domains' report shows low-DR linking domains which are often spam sources.
- SEMrush Backlink Audit: dedicated backlink toxicity audit tool that assigns a toxicity score to each linking domain. Integrates with Google Disavow tool directly. Paid plans required.
- Google Search Console: free and directly from Google. Does not show spam score but shows all links to your site. Use the 'Links' report to manually inspect linking domains for obvious spam.
Free Spam Score Checker Tools — Compared
| Tool | Cost | Best For | Key Capability |
|---|---|---|---|
| Moz Link Explorer | Free (10/mo) / Paid from $99/mo | Most accurate spam score | Original spam score metric. Full 27-flag breakdown. Historical tracking. Most authoritative source. |
| SmallSEOTools Checker | Free, no sign-up | Quick bulk checks | Check multiple URLs at once using Moz data. Export results to Excel. No account needed. |
| DA PA Checker (dapachecker.org) | Free, no sign-up | Checking 5 URLs at once | Shows spam score, DA, and PA simultaneously. Good for quick pre-outreach checks. |
| SEMrush Backlink Audit | Paid from $129/mo | Deep toxic link analysis | Assigns individual toxicity scores to each backlink. Integrates directly with Google Disavow. |
| Ahrefs Site Explorer | Paid from $99/mo | Backlink profile analysis | Uses Domain Rating (DR) rather than Moz spam score. Superior for identifying low-DR linking domains. |
| Google Search Console | Free | Checking all inbound links | Free from Google. No spam score metric, but shows all links. Use as a free starting point for link audits. |
Toxic Backlinks: Data Fields, Toxicity Reasons & Categories
When SEO tools identify toxic backlinks, they report a set of specific data fields, toxicity reasons, and link categories. Understanding what each one means helps you decide which links to disavow and which are safe to ignore.
Toxic backlink data fields — what each metric means
| Data Field | What It Tells You |
|---|---|
| Source URL | The exact page on the linking website that contains the link to your site. This is the URL you would target in a disavow file. |
| Source Domain | The root domain of the linking website. If multiple toxic pages from the same domain are linking to you, disavow the domain, not individual URLs. |
| Spam Score | Moz's percentage (0–100%) for the linking domain. Links from domains with spam score above 30–40% should be reviewed carefully. |
| Domain Authority (DA) | Moz's measure of the linking domain's overall authority. A link from a DA 2 site with 80% spam score is a classic toxic link pattern. |
| Anchor Text | The visible text of the link pointing to your site. Over-optimised, exact-match anchor text from low-quality sites is a spam signal. |
| Link Type | Dofollow or nofollow. Dofollow links pass authority — toxic dofollow links cause more harm than nofollow ones. |
| First Seen / Last Seen | When the link was first detected and last confirmed active. Useful for identifying sudden backlink spikes — a sign of negative SEO. |
| Toxicity Score | SEMrush's own metric (0–100) for how likely a link is to harm your rankings. Different methodology from Moz's spam score but measures similar signals. |
Toxicity reasons — why a tool flags a backlink as toxic
| Toxicity Reason | Explanation |
|---|---|
| Low domain authority + high spam score | The linking domain has both low authority (DA under 10) and high spam score (above 40%). This combination is the strongest indicator of a toxic link. |
| Unnatural anchor text patterns | Exact-match commercial anchor text on a low-quality site. Natural links use brand names, URLs, or generic text. |
| Link farm or PBN pattern | The linking site links out to hundreds of unrelated websites with commercial anchor text — a classic private blog network (PBN) or link farm signal. |
| Thin or auto-generated content | The linking page has very little original content, often scraped or auto-generated. Google and Moz both flag links from these pages. |
| Sudden link spike | A large number of links from a domain appeared within days. Natural links accrue gradually. Sudden spikes suggest manipulation or negative SEO. |
| IP diversity issues | Multiple links from sites hosted on the same IP address or subnet — a sign of link network activity. |
| Country/language mismatch | Links from foreign-language sites with no relevance to your niche or geography. Often indicate purchased link schemes. |
| No-index or low-crawl pages | The linking page is set to noindex or rarely crawled — suggesting it exists only to pass links, not to serve users. |
Backlink categories — types of links most commonly flagged
| Category | Description and What to Do |
|---|---|
| Link farm links | Sites created solely to host outbound links. No real content, no real audience. Disavow all links from confirmed link farms immediately. |
| Private blog network (PBN) links | Expired domains bought to build link networks. Often have DA but show unnatural link patterns. Disavow if you did not intentionally acquire these links. |
| Footer and sitewide links | A link in a website's footer appears on every page — giving you hundreds or thousands of links from one low-quality domain. One domain-level disavow handles all. |
| Forum spam links | Links from automated forum posts, blog comments, or profile pages. Often dofollow and from low-quality domains. |
| Scraped content links | Automatically scraped versions of your content on low-quality aggregator sites. The link exists but comes from zero-authority, often penalised domains. |
| Paid or unnatural link schemes | Links purchased or exchanged in violation of Google's guidelines. Removing them proactively is better than waiting for a manual action. |
| Irrelevant niche links | Links from sites in completely unrelated industries with no logical reason to link to you. Combined with other signals, they raise your score. |
Spam Score vs Toxic Score: What Is the Difference?
Two terms are often confused in SEO conversations: spam score and toxic score. They measure related but distinct things, and they come from different tools.
| Spam Score (Moz) | Toxic Score (SEMrush) | |
|---|---|---|
| Created by | Moz | SEMrush |
| Scale | 0% – 100% | 0 – 100 |
| What it measures | Likelihood of a website being penalised based on 27 spam flags including backlink patterns, content signals, and on-page characteristics | Likelihood that a specific backlink is harmful to your rankings, based on 45 toxic markers including anchor text, linking domain quality, and link context |
| Applied to | Entire domains | Individual backlinks pointing to your site |
| How to access | Moz Link Explorer (free tier available) | SEMrush Backlink Audit tool (paid subscription required) |
| Best use case | Quick domain-level spam risk assessment; evaluating sites before accepting a backlink | Deep backlink audits; building a disavow file for Google; recovering from penalties |
In practice, most SEO teams use both: spam score for quick domain-level checks (e.g., before accepting a guest post opportunity) and toxic score for deep backlink audits when a site has been penalised or has seen a ranking drop.
What Is a Good Spam Score?
A good spam score is one below 30% — this is the low-risk range where 92.6% of websites sit according to Moz's own data. For most SEO purposes, anything under 10% is excellent, and a score under 5% is considered ideal for sites that actively build backlinks.
| Score | Assessment | What to Do |
|---|---|---|
| 0% – 10% | Excellent | Your site is in excellent shape. No action needed — continue building quality backlinks and monitor quarterly. |
| 11% – 30% | Good | Within the safe range. Review your backlink profile annually. No urgent action required unless your score has increased rapidly. |
| 31% – 50% | Medium risk | Worth investigating. Run a full backlink audit in Moz or SEMrush, identify the sources of concern, and disavow the clearest offenders. |
| 51% – 70% | High risk | Take action now. Conduct a full backlink audit and submit a disavow file to Google. Consider a technical SEO audit too. |
| 71% – 100% | Critical | Immediate action required. A Google manual action or algorithmic penalty may already be in effect. Audit, disavow, and review all on-page signals. |
Context matters: A high spam score does not automatically mean your site will be penalised. Moz itself notes that many high-scoring sites never receive a Google penalty. Spam score is a useful early-warning indicator, not a verdict. Use it as a starting point for investigation, not a source of panic.
Top Spam Score Signals (Moz Flags Explained)
Moz's spam score is calculated from 27 specific signals, called spam flags. Not all 27 are publicly disclosed, but the most commonly triggered ones — and the most impactful — are these five. Each one directly increases your spam score percentage when it applies to your site.
1. Low Link Equity Relative to Site Size (Moz flag: 'few links to site')
A site with hundreds of pages but very few inbound links signals that its content has attracted no natural attention. Search engines have learned that genuinely useful, well-regarded content attracts links over time. A site that grows its page count without growing its link profile is a pattern commonly seen in low-quality content farms and auto-generated sites. If your site has grown significantly in page count recently without a corresponding increase in referring domains, this flag is likely triggered.
2. Poor Link Diversity (Moz flag: 'links from few domains')
If the majority of your inbound links come from a small number of domains — regardless of how many total links you have — this signals an unnatural linking pattern. For example, 500 inbound links from just 5 domains suggests those links were placed deliberately rather than earned naturally. Healthy link profiles have hundreds or thousands of unique referring domains, each contributing a small number of links. A ratio of fewer than 1 unique domain per 10 inbound links is a common spam flag threshold.
3. Unnatural Dofollow-to-Nofollow Ratio
Naturally acquired links tend to be a mix of dofollow and nofollow — blog comments, social shares, forum posts, and journalist citations often generate nofollow links. A backlink profile that is almost entirely dofollow suggests that the links were acquired through methods designed to pass PageRank (link schemes, PBNs, paid links) rather than earned organically. Moz flags sites where the dofollow ratio is disproportionately high relative to their total link count and domain age.
4. Minimal Site Markup and Technical Signals
Legitimate websites invest in proper HTML structure, schema markup, CSS, and JavaScript for functionality and user experience. Sites built purely to host content or pass links often have minimal markup — basic HTML with no schema, no structured CSS, and no interactive elements. Moz identifies this as a spam signal because it is a pattern consistently observed in low-quality, mass-produced sites. Ensure your site has proper schema markup, a structured CSS framework, and all standard technical elements.
5. Low Internal Link Density
Websites with substantial, high-quality content naturally develop dense internal linking structures — each piece of content links to related resources, guiding users through the site. Sites with little internal linking typically have thin, isolated pages with no topical connections. Low internal link density combined with other spam flags (particularly low external links) significantly raises a site's spam score. Review your internal linking strategy and ensure every page links to at least 3–5 relevant internal resources.
Spam Score After Google's 2025–2026 Updates
Google's approach to web spam has evolved significantly since the March 2024 spam update. Here is what has changed and how it affects how you should interpret and act on your spam score:
March 2024 Spam Update — What It Targeted
Google's March 2024 spam update had three primary targets: expired domain abuse (buying expired domains to exploit their historical authority for hosting low-quality content), scaled content manipulation (producing large volumes of unoriginal content to game rankings), and site reputation abuse (third-party content published on reputable sites to benefit from host authority). Sites engaging in these practices saw significant ranking drops, and many with high spam scores in these areas were algorithmically penalised.
2025 Updates — AI Content and Link Quality Signals
Google's 2025 algorithm updates placed increased emphasis on content originality and genuine expertise. Sites with high spam scores due to thin or auto-generated content faced stronger headwinds in ranking. More importantly, Google's link quality assessments became more sophisticated — the same types of links that Moz's spam score penalises (PBNs, link farms, sitewide footer links) increasingly trigger Google's own algorithmic link devaluation, meaning those links simply stopped passing authority rather than causing direct penalties.
2026 — What to Watch
As of early 2026, the trend is toward site-level quality assessments rather than purely link-based penalties. Sites with high spam scores due to low-quality content and poor user experience signals are at increasing risk from Google's core quality updates, even if they do not receive a specific spam-related manual action. Monitoring your spam score has become a proxy for monitoring the overall health signals Google uses to evaluate site quality.
Monitoring and managing your spam score is a non-negotiable part of maintaining your site's long-term SEO health. A high spam score does not fix itself — it requires a systematic backlink audit, targeted disavow submissions, and ongoing monitoring to keep your link profile clean.
If your spam score has increased recently, if you have seen a drop in organic rankings, or if you want a professional assessment of your site's overall link health and technical SEO, Cronbay's SEO team provides full backlink audits, disavow file preparation, and ongoing SEO monitoring for clients across India, Singapore, and the UAE.
Get a free website SEO audit — including spam score analysis, backlink health, and technical SEO checks.
Visit cronbay-tech.com/webaudit/ or call +91 8904366659.
Frequently Asked Questions
Q1. What is a good spam score for a website?
Ans. A spam score below 30% is considered low risk and acceptable for most websites. A score under 10% is excellent. Between 31–60% is medium risk and warrants a backlink audit. Above 60% is high risk and requires immediate action. According to Moz's own data, 92.6% of websites have a spam score in the low-risk range (1–30%). A score above this range does not guarantee a Google penalty, but it indicates your site has characteristics commonly found in penalised websites.
Q2. How do I check the spam score of my website?
Ans. The most accurate method is Moz Link Explorer (moz.com/link-explorer). Create a free account, enter your domain URL, and navigate to the Spam Score tab. You will see your overall spam score and a breakdown of the specific spam flags triggering it. For a quick free check without sign-up, use smallseotools.com/spam-score-checker/ or dapachecker.org/spam-score-checker — both use Moz data and check multiple URLs simultaneously.
Q3. Is spam score a direct Google ranking factor?
Ans. No. Spam score is a Moz metric — it is not used by Google in its ranking algorithm. However, the signals that Moz's spam score measures (toxic backlinks, thin content, unnatural link patterns) are the same signals that Google's own algorithms evaluate. A high spam score is a useful warning indicator that your site may have characteristics Google independently penalises.
Q4. What causes a high spam score?
Ans. The most common causes are toxic or low-quality backlinks (links from link farms, PBNs, spam sites, or irrelevant sources), unnatural anchor text patterns, thin or auto-generated content, poor site markup and technical signals, and low internal linking density. Spam score is calculated from 27 flags that Moz identified by analysing websites that had been penalised or deindexed by Google.
Q5. How do I reduce my website's spam score?
Ans. The most impactful steps are: (1) Conduct a full backlink audit using Moz Link Explorer or SEMrush Backlink Audit. (2) Identify links from low-authority, high-spam-score domains. (3) Attempt to remove toxic links by contacting linking site owners. (4) Submit a Google Disavow file for links you cannot get removed. (5) Improve content quality — thin, duplicate, or auto-generated content also triggers spam flags. (6) Build legitimate backlinks from relevant, high-authority sources to dilute the proportion of toxic links in your profile.
Q6. What is the difference between spam score and toxic score?
Ans. Spam score is a Moz metric (0–100%) that assesses the overall spam risk of an entire domain based on 27 signals. Toxic score is a SEMrush metric (0–100) that assesses the potential harm of an individual backlink pointing to your site based on 45 toxic markers. In practice: use spam score for quick domain-level checks and toxic score for deep backlink audits when building a disavow file.
Q7. How often should I check my spam score?
Ans. For most websites, a monthly check is sufficient. If you are actively building backlinks, check every two weeks. If you have recently seen a ranking drop or suspect negative SEO, check immediately and set up monthly monitoring. Spam score can change when new backlinks are detected — both positively and negatively.
Q8. Can spam score go down on its own?
Ans. Yes, but it usually requires action. Spam score decreases when toxic backlinks are removed by the linking site, when you successfully submit a Google Disavow file, or when you build enough high-quality backlinks to reduce the proportion of toxic links in your profile. Simply waiting for spam score to improve on its own is not a reliable strategy — especially if your site is receiving active negative SEO.
Q9. What are SEO tool toxic backlinks spam score data fields, toxicity reasons and categories?
Ans. When SEO tools like Moz and SEMrush analyse toxic backlinks, they report several data fields per link: source URL and domain, spam score of the linking domain, domain authority, anchor text, link type (dofollow/nofollow), and first/last seen dates. Toxicity reasons are the specific signals that flagged the link — such as low DA combined with high spam score, unnatural anchor text, link farm patterns, or PBN characteristics. Backlink categories describe the type of link — link farm, PBN, footer/sitewide, forum spam, scraped content, or paid link scheme.
Q10. What should I do after finding a high spam score?
Ans. Step 1: Do not panic — high spam score is a warning signal, not a confirmed penalty. Step 2: Export your full backlink list from Moz Link Explorer. Step 3: Filter for links from domains with spam score above 40% and DA below 20. Step 4: Attempt manual removal by contacting linking site owners. Step 5: For links you cannot remove, submit a Google Disavow file at search.google.com/search-console/disavow-links. Step 6: Re-check your spam score 30 days after submitting the disavow file to track improvement.
