# SEO Backlinks > Off-page/backlink audit: link-profile analysis, referring-domain quality, anchor-text distribution, toxic-link detection, disavow guidance, expired-domain heritage risk, parasite-SEO exposure, and digital-PR link earning. Use when auditing or building backlinks, assessing a link profile, judging link toxicity, or planning link acquisition. Triggers on: backlinks, link profile, referring domains, anchor text, toxic links, disavow, link gap, link building, digital PR, expired domain, parasite SEO, off-page SEO. - Skill: `pixartseu/seo-backlinks` (Agent Skill) - Install (CLI): `npx skillmds@latest add pixartseu/seo-backlinks` - Raw SKILL.md: https://api.skillmd.com/api/skills/pixartseu/seo-backlinks/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Marketing & Growth - Author: PIXARTSeu (https://skillmd.com/u/pixartseu) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/pixartseu/seo-backlinks --- # Backlink / Off-Page SEO Audit Off-page SEO is the part of ranking you do not fully control: who links to a site, with what anchor text, and how trustworthy those sources are. This skill is an **audit + acquisition methodology**, not a vendor wrapper. Backlink discovery needs a crawl of the web's link graph, which no public crawler gives in full — so the metrics here depend on a **backlink data source** (a backlink API, search-console link export, or an open web-graph dataset). See the `seo-rank-data` skill for sourcing that data and its confidence weighting. Everything below is the analysis you run *on top of* that data. ## When to use - Auditing why a site under- or over-performs vs. its link profile. - Vetting a domain before purchase (expired/aged domain heritage risk). - Detecting toxic links and deciding whether to disavow. - Finding link-building opportunities (competitor gap, digital PR). - Checking exposure to parasite-SEO / negative-SEO patterns. ## Data sources and confidence You will almost never have a complete link graph. Label every metric with its source and a confidence weight, and never present an inferred number as a measured fact. | Source | What it gives | Confidence | Freshness | |--------|---------------|------------|-----------| | Commercial backlink API (e.g. a SaaS index) | Backlinks, referring domains, authority, anchors, follow ratio, velocity | 1.0 | days–weeks | | Search Console link export (own site only) | Top linking sites + anchors (sampled, no authority) | 0.85 | ~days | | Open web-graph dataset (e.g. Common Crawl) | Domain-level in-degree, harmonic centrality, top referrers (no authority scores) | 0.5 | quarterly | | Live verification crawl (your own crawler) | Whether a *known* backlink still exists, follow/nofollow, anchor | 0.95 | real-time | **Data sufficiency gate (falsifiability):** of the 7 scored factors below, count how many have at least one source. If fewer than 4 are covered, do **not** emit a numeric 0–100 score — emit `INSUFFICIENT DATA (X/7 factors)` plus the factor scores you do have. A confident number built on one weak source reads as "poor health" when the truth is "we lack data". When only an open web-graph dataset is available, cap the score at 70/100. ## Audit framework (produce all 7 sections) ### 1. Profile overview Pull totals: backlinks, referring domains, follow ratio, authority/rank, trend. | Metric | Good | Warning | Critical | |--------|------|---------|----------| | Referring domains | >100 | 20–100 | <20 | | Follow ratio | >60% | 40–60% | <40% | | Single-domain concentration | no domain >5% of links | one domain >10% | one domain >25% | | Trend | growing or stable | slow decline | rapid decline (>20%/quarter) | ### 2. Anchor-text distribution Over-optimized anchors are the classic algorithmic-penalty (Penguin-lineage) signal. | Anchor type | Healthy range | Over-optimization flag | |-------------|---------------|------------------------| | Branded (company/domain) | 30–50% | <15% (looks built, not earned) | | Naked URL | 15–25% | — | | Generic ("click here", "read more") | 10–20% | — | | Exact-match keyword | 3–10% | **>15%** | | Partial-match keyword | 5–15% | >25% | | Long-tail / natural sentence | 5–15% | — | Flag exact-match anchors over 15%, especially when concentrated from few domains — that is a manipulation fingerprint, not natural editorial linking. ### 3. Referring-domain quality - **TLD mix:** .edu/.gov/.org skew authoritative; a flood of cheap .xyz/.top/.info skews spam. - **Geo mix:** should roughly match the target market; 80%+ from irrelevant countries is a PBN tell. - **Authority spread:** healthy profiles have links across all authority tiers, not only the top. - **Per-domain follow/nofollow:** domains that *only* nofollow pass branding but little ranking value. ### 4. Toxic-link detection High-risk patterns (flag immediately, candidates for disavow): - Private Blog Network (PBN) footprints: shared hosting/IP, identical themes, thin reciprocal money sites. - 100% exact-match anchors from a single domain. - Links from penalized or deindexed domains. - Mass directory dumps (50+ low-quality directory links). - Link farms / pages with 10k+ outbound links. - Sitewide footer/sidebar links across an entire domain (paid-link footprint). Medium-risk (review manually before acting): - Links from unrelated niches; reciprocal A↔B patterns; links from thin pages (<100 words); >50 backlinks all from one domain. ### 5. Expired / aged-domain heritage risk Before buying or migrating onto an aged domain, audit its *past life* — Google carries history forward, and a domain can arrive pre-penalized. - Pull historical snapshots (web archive) for prior content: was it a real site, or a spam/PBN/adult/gambling flip? - Check the existing backlink profile against sections 2–4 *before* relaunch. - Confirm it was not previously deindexed; verify a clean reindex after relaunch. - A domain with strong raw metrics but a toxic anchor profile or off-niche history is a liability, not a shortcut. ### 6. Parasite-SEO / negative-SEO exposure - **Parasite SEO (inbound risk):** spam pages hosted on a high-authority host (UGC subdomains, open profile/forum pages, abandoned subfolders) can borrow your authority. Audit subdomains and user-generated areas for content you did not publish. - **Negative SEO:** a sudden spike of toxic links pointed at you. The defense is the *velocity* baseline in section 7 — without it you cannot tell an attack from organic growth. ### 7. Link velocity & gap - **New/lost links over 30/60/90 days** (needs a time-series source). Watch for: unexplained spikes (possible negative-SEO injection), mass losses (penalty or content removal), and steadily declining velocity (content no longer earning links). - **Competitor gap:** domains linking to a competitor but *not* to the target = the prioritized acquisition list; domains linking to both = relationships to deepen. ## Backlink health score (0–100) | Factor | Weight | Preferred source order | |--------|--------|------------------------| | Referring-domain count | 20% | API > web-graph in-degree | | Domain-quality distribution | 20% | API authority > web-graph centrality | | Anchor-text naturalness | 15% | API > Search Console anchors | | Toxic-link ratio | 20% | API spam signals > verification crawl | | Link-velocity trend | 10% | API time-series only | | Follow/nofollow ratio | 5% | API > verification crawl | | Geographic relevance | 10% | API country data | Score each factor 0–100, weight, sum. Redistribute the weight of any unsourced factor proportionally across the rest. Always print which factors were scored vs. skipped, with their source and confidence — apply the sufficiency gate from above before showing a number. ## Falsifiability check (run before delivering) State, for every material claim, **how you would know it was wrong** and the **leading indicator** to watch. | Claim | How would we know it's wrong? | Leading indicator | |-------|-------------------------------|-------------------| | "This link is toxic / disavow it" | Disavowing a borderline link drops a ranking it was actually helping | Track rankings 4–8 weeks post-disavow; disavow conservatively, in batches | | "We have a toxic-anchor problem" | The over-optimized anchors come from scraper copies of one real editorial link, not built links | Group anchors by *root domain*, not by raw count | | "Link removed" | The page is JS-rendered and the `` exists post-hydration | Mark `unverifiable_js` instead of `removed` when the source is an SPA shell | | "Negative-SEO attack" | The spike is a legitimate viral/PR event | Compare against the velocity baseline + check anchor/topic relevance of new links | | "This aged domain is safe to buy" | Post-relaunch it fails to index or rankings never materialize | Verify reindex + run a fresh profile audit 30 days after relaunch | | "Referring-domain count = N" | N counts links, or counts duplicate subdomains as distinct | Deduplicate to registrable domains; reconcile summary vs. the verified link list | If any check fails, fix the finding before reporting. Distinguish "not crawled" vs. "below threshold" vs. "error" — never collapse them into "not found". ## Disavow guidance Disavow is a last resort, scoped to **manipulative links you cannot get removed**. 1. Attempt manual removal first (outreach to the linking site). 2. Disavow at **domain** level (`domain:example.com`) for whole-domain spam; per-URL only for surgical cases. 3. Keep it conservative — disavowing healthy links removes ranking signal. Re-measure after 4–8 weeks. 4. Google's own guidance: most sites never need a disavow file; the algorithm ignores most spam automatically. ## Link earning (digital PR — the durable strategy) The only links that survive algorithm updates are *editorially earned*. Prioritize creating link-worthy assets over chasing volume: - **Original data / research:** surveys, benchmarks, "state of X" reports — journalists cite primary data. - **Free tools & calculators:** a small Next.js utility page earns links passively for years. - **Expert commentary / reactive PR:** respond to journalist requests in your niche. - **Genuinely useful long-form** that becomes the canonical reference for a query. For our stack, ship link-bait assets as fast, indexable RSC routes: ```tsx // app/[locale]/tools/roi-calculator/page.tsx — a linkable free-tool page (RSC + client island) import type { Metadata } from "next"; import { getTranslations } from "next-intl/server"; import { Calculator } from "./calculator"; // "use client" island for interactivity export async function generateMetadata( { params }: { params: Promise<{ locale: string }> }, ): Promise { const { locale } = await params; const t = await getTranslations({ locale, namespace: "roiTool" }); const url = `${process.env.NEXT_PUBLIC_SITE_URL}/${locale}/tools/roi-calculator`; return { title: t("title"), description: t("description"), alternates: { canonical: url }, // stable canonical = links consolidate to one URL openGraph: { url, title: t("title"), description: t("description") }, }; } export default function Page() { // Server-render the explanatory copy (crawlable, link-worthy); // hydrate only the interactive widget. Keeps the asset fast + indexable. return (

ROI Calculator

); } ``` JSON-LD that makes original research citable (helps journalists and AI assistants attribute you): ```tsx // Inline in the asset page's RSC body const jsonLd = { "@context": "https://schema.org", "@type": "Dataset", name: "2026 SaaS Onboarding Benchmark", description: "Survey of 1,200 B2B SaaS onboarding flows.", creator: { "@type": "Organization", name: "Your Org" }, license: "https://creativecommons.org/licenses/by/4.0/", url: `${process.env.NEXT_PUBLIC_SITE_URL}/research/onboarding-2026`, }; //