Backlink Checker API — Referring Domains, Competitor Gap & Backlink Profile · Ahrefs / Semrush Alternative

Enter a domain, get its full backlink profile via API — total backlinks, referring domains, spam score, and the competitor backlink gap: the domains that link to your rivals but not to you. Pay per result, no $99–$199/month subscription, no contract. Native backlink-index data via API — not a fragile UI scraper.

Coverage on par with Ahrefs — measured, not claimed. In side-by-side tests our referring-domain coverage matched or beat Ahrefs: an established site returned 1,737 referring domains vs Ahrefs' 1,600; a brand-new site 43 vs 32. You get a credible backlink index at a fraction of a tool subscription. (We don't reproduce Ahrefs' proprietary DR score — see FAQ.)

Built for link builders, SEO & PR agencies, sales / lead-gen teams, and developers wiring backlink data into pipelines via API or MCP.

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⚡ Quick start — 30 seconds

Click Try for free. The default input runs a real backlink summary on a live domain — actual JSON in seconds. Then swap in your own:

{ "domains": ["monday.com"], "mode": "summary" }

Sample output (real run, trimmed):

{
  "mode": "summary",
  "target": "monday.com",
  "rank": 644,
  "backlinks": 8975219,
  "referring_domains": 72896,
  "referring_main_domains": 63603,
  "referring_domains_nofollow": 9683,
  "broken_backlinks": 138276,
  "backlinks_spam_score": 19,
  "first_seen": "2019-01-15"
}

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🎯 Three modes

mode	Input	One dataset row per target
summary (default)	domains	full profile: rank, backlinks, referring domains (total / main / nofollow), broken backlinks, spam score, first seen
referring_domains	domains, limit	ranked list — each { domain, rank, backlinks, spam score, first seen }
competitor_gap ⭐	domains, competitors, limit	domains that link to your competitors but not to you — your ready-made link-building target list

competitor_gap is the one no free tool gives you. Drop in 2–3 rivals and get the exact referring domains you're missing — the highest-intent link-prospecting list there is.

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🚀 Input

field	type	default	notes
domains	string[]	— (required)	target domains; auto-normalized (scheme/path/www. stripped, IDN→punycode, lowercased) and deduped
mode	enum	summary	summary | referring_domains | competitor_gap
competitors	string[]	—	required for competitor_gap; rival domains
limit	int (1–1000)	100	rows for the list modes (ignored by summary)
includeSubdomains	bool	true	count subdomains toward the target

// referring domains — top 50 by rank
{ "domains": ["monday.com"], "mode": "referring_domains", "limit": 50 }

// competitor gap — who links to asana & clickup but not monday
{ "domains": ["monday.com"], "mode": "competitor_gap",
  "competitors": ["asana.com", "clickup.com"], "limit": 100 }

📊 Output

One dataset item per target domain:

• summary → { target, rank, backlinks, referring_domains, referring_main_domains, referring_domains_nofollow, broken_backlinks, backlinks_spam_score, first_seen }
• referring_domains → { target, count, referring_domains_list: [{ domain, rank, backlinks, backlinks_spam_score, first_seen }] }
• competitor_gap → { target, competitors, gap_count, gap: [{ domain, rank, links_to[] }] }

Export as JSON / CSV / Excel, or pull live via the Apify API (run-sync-get-dataset-items).

💰 Pricing — pay per result, flat per report

You pay per domain, not per row — same price whether you pull 20 rows or 1,000.

event	price / domain	when
actor-start	$0.005	once per run, after input validation
domain-summary	$0.15	after a successful summary
referring-domains-report	$0.20	after a successful referring-domains list (any limit)
competitor-gap-report	$0.25	after a successful competitor-gap report (any limit)

Charged only after data is delivered — failed or empty calls bill nothing beyond actor-start. A per-run cost cap (MAX_RUN_COST_USD, default $5) stops the run before overspend.

Example: a competitor gap on your domain vs 2 rivals (top 100 prospects) = $0.005 + $0.25 = $0.255. The same workflow in Ahrefs/Semrush needs a $99–$199/month seat.

Free Apify plan: capped to 1 domain, summary mode per run — you still see your domain's real profile (referring-domain count, broken links, spam score). Popular domains return instantly from a built-in preview cache; any other domain gets one real live summary so you can preview your own site. The ranked referring-domains list and the competitor gap require a paid plan.

🆚 How it compares

vs. Ahrefs / Semrush / Moz — no $99–$199/month subscription; pay per domain checked. API-first JSON straight into your sheet, CRM, n8n/Make/Zapier, or AI agent. Referring-domain coverage on par (measured). Trade-off: we don't reproduce Ahrefs' proprietary DR — we return a 0–1000 domain rank + backlink spam score.

vs. other Apify backlink actors — most scrape the Ahrefs/Semrush UI: fragile (break on UI change), ToS-risky, only as available as the SaaS login. This actor uses a native data API — stable, no scraping, no proxy roulette — and adds a value layer (competitor gap, spam signal, clean typed output, free preview).

vs. raw data-API providers — no monthly minimum commitment, no API-key management, no per-endpoint billing math. Pay per result, scale to zero.

🧭 Who it's for

• Link builders / SEO agencies — competitor_gap = instant prospecting list; referring_domains = profile audit.
• Content & PR teams — see who links to the competition, pitch the same outlets.
• Sales / lead-gen — a rival's referring domains are warm outreach signals.
• Developers & AI agents — backlink data as a clean JSON API / MCP tool, billed per call.

🔌 API & integrations

Run from the Apify API (incl. run-sync-get-dataset-items for a single request/response call), official JS / Python clients, CLI, or any HTTP client — see the API tab. Pipe results to Google Sheets, Slack, n8n, Make, Zapier via Apify integrations. (MCP server for AI agents on the roadmap.)

🛡️ Legal & compliance

Uses a licensed native backlink data API. Public link-graph data only — no login-walled or personal data. ToS-safe (no identical-request hammering; built-in run cache).

🧰 FAQ

Is the coverage as good as Ahrefs? On referring domains, yes in our tests (1,737 vs 1,600 established; 43 vs 32 new). Backlink indexes never match exactly — we surface a credible, native index at pay-per-result pricing.

Do you return Domain Rating (DR)? No — DR is Ahrefs' proprietary score. We return a domain rank (0–1000) + backlink spam score for relative authority/quality.

How am I billed? Per result, after delivery (see Pricing). Free / failed / empty calls don't bill beyond actor-start. A per-run cost cap prevents surprises.

Where does the data come from? A licensed, enterprise-grade backlink-data API — not a UI scraper. Stable, no proxies.

Can it monitor new / lost backlinks? On the roadmap (v0.2) — scheduled new/lost diffs + alerts. v1 is on-demand lookups.

🗺️ Roadmap

v0.2: new/lost backlink monitoring (scheduled diffs + Slack/email alerts), anchor-text breakdown, bulk mode (≤1000 domains/call), disavow-list export. + MCP server for AI agents.

🏷️ Keywords

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🤝 Built by

doesaiknow — semantic-SEO & LLM-search APIs on Apify Store. Pay-per-result, no subscription, MCP-ready. More tools:

• Keyword Search Volume API — Google + Bing search volume, CPC & 12-month trends, bulk.
• AI Keyword Clustering Tool — cluster up to 1,000 keywords into a SERP-validated topical map.
• AI Brand Visibility Tracker — see where your brand shows up in ChatGPT, Perplexity & Gemini answers.