Backlink Checker API — backlinks, referring domains & competitor link gap (Python, Node.js, cURL)

Get every backlink to any domain or page (linking URL, anchor text, dofollow/nofollow, authority, first/last seen) as JSON or CSV. Find link-gap prospects: websites that link to your competitors but not to you. $1 per 1,000 backlinks, no Ahrefs or Semrush subscription.

It uses the Backlink Checker on Apify, which reads a commercial backlink index. Filters (dofollow only, one link per domain, minimum authority, anchor text) are applied at the source, so you only pay for rows you keep.

📖 Tutorial: Find link-building prospects with Python: a competitor backlink gap

Quick start (Python)

pip install "apify-client>=3"
export APIFY_TOKEN=your_token   # free account at https://console.apify.com

from apify_client import ApifyClient

client = ApifyClient("YOUR_APIFY_TOKEN")
run = client.actor("jesting_grass/backlink-checker").call(run_input={
    "mode": "backlinks",
    "targets": ["allbirds.com"],
    "maxResultsPerTarget": 200,
    "onePerDomain": True,
    "dofollowOnly": True,
})
for row in client.dataset(run.default_dataset_id).iterate_items():
    print(row["domainRank"], row["sourceUrl"], row["anchor"])

Real output (September 2026, first rows):

domainRank	pageRank	linking page	anchor
88	17	pinterest.com/weareallbirds/	allbirds.com
84	0	pay.amazon.com/blog/for-shoppers/possible-with-pay-9-eco-friendly-brands-for-more-sustainable-shopping	AllBirds

Competitor link gap

link_gap_prospects.py compares the top 1,000 referring domains of allbirds.com, rothys.com and vivobarefoot.com, and keeps sites that link to both competitors but not to Allbirds. Real output:

medium.com                     rank 75   links to rothys.com, vivobarefoot.com
app.welcometothejungle.com     rank 65   links to rothys.com, vivobarefoot.com
storeleads.app                 rank 64   links to rothys.com, vivobarefoot.com
prnewswire.com                 rank 64   links to rothys.com, vivobarefoot.com
shows.acast.com                rank 62   links to rothys.com, vivobarefoot.com
zoominfo.com                   rank 59   links to rothys.com, vivobarefoot.com
player.fm                      rank 57   links to rothys.com, vivobarefoot.com
...

A site that already links to two of your competitors covers your niche, which makes it a strong outreach target.

Examples

File	What it does
backlinks_to_csv.py	Backlinks of a domain (dofollow, one per linking site) → backlinks.csv
link_gap_prospects.py	Sites linking to your competitors but not to you
node.js	Backlinks in Node.js
curl.sh	One HTTP call, JSON back

Modes and output fields

Mode	Fields
backlinks	sourceUrl, sourceDomain, targetUrl, anchor, dofollow, isImageLink, sourcePageTitle, domainRank, pageRank, firstSeen, lastSeen
referringDomains	referringDomain, domainRank, firstSeen (+ backlinks, dofollowBacklinks when reported)
linkGap	referringDomain, domainRank, linksToCompetitors, competitorsLinked

domainRank / pageRank are 0–100 authority scores from the backlink index (similar in spirit to Ahrefs DR/UR or Moz DA/PA, not identical).

Ahrefs vs Semrush vs this

	Ahrefs	Semrush	This
Price	Lite from $129/month	SEO plan from $139/month	$1 per 1,000 backlinks, no subscription
Individual backlinks, bulk export	yes	yes	yes, up to 10,000 per target per run
Competitor link gap	Link Intersect	Backlink Gap	linkGap mode
Works from n8n / Make / Zapier / AI agents	API on higher plans	API on higher plans	yes, plus Apify MCP server

Prices as listed on the vendors' pricing pages in September 2026 (monthly billing).

More SEO tools from the same developer

• Bulk Domain Authority Checker API: domain rank and backlink totals for 1,000s of domains
• Keyword Research API: search volume, keyword difficulty, intent and AI Overviews
• Google Trends API: interest over time, rising queries and regions
• BuiltWith & Wappalyzer alternative: tech stack of any website in bulk

Not affiliated with Ahrefs, Semrush or Moz; names are used for comparison only. Examples are MIT licensed.