Backlinks

One call that summarises a domain's link profile. Use it to size a competitor's authority before deciding whether to compete on content or on links.

POST/v1/domains/backlinks

Backlinks summary

Totals for the whole domain including subdomains, with internal links excluded.

Costs 8.3 credits per call.

Required attributes

Name
domain
Type
string
Description
A bare domain such as example.com. Protocol, www. and paths are stripped.

Response fields

Name
rank
Type
integer
Description
Domain rank from 0 to 1000, based on the quality and quantity of links.
Name
referring_domains
Type
integer
Description
Distinct domains linking to the target. Usually the number that matters.
Name
nofollow_backlinks
Type
integer
Description
Links carrying rel=nofollow.
Name
spam_score
Type
integer
Description
0 to 100. Higher means more links from suspicious sources.
Name
top_tlds
Type
array
Description
Top level domains of the linking sites, by link count.
Name
link_types
Type
array
Description
anchor, image, redirect, canonical and so on.
Name
top_countries
Type
array
Description
Countries of the linking sites, by link count.

Request

POST

/v1/domains/backlinks

curl -X POST https://suvjexogmfpvxjcktvuk.supabase.co/functions/v1/api/v1/domains/backlinks \
  -H "Authorization: Bearer $PENGU_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"domain": "hubspot.com"}'

Response

{
  "data": {
    "domain": "hubspot.com",
    "checked_at": "2026-09-09T11:47:23.500Z",
    "rank": 679,
    "backlinks": 29053738,
    "referring_domains": 384860,
    "referring_main_domains": 333298,
    "referring_ips": 129902,
    "referring_pages": 22169548,
    "broken_backlinks": 186430,
    "broken_pages": 174114,
    "nofollow_backlinks": 966161,
    "sponsored_backlinks": 14181,
    "spam_score": 5,
    "first_seen": "2019-01-15 22:57:10 +00:00",
    "top_tlds": [
      {
        "name": "com",
        "count": 14879506
      },
      {
        "name": "org",
        "count": 751402
      },
      {
        "name": "blogspot.com",
        "count": 512841
      },
      // ...
    ],
    "link_types": [
      {
        "name": "anchor",
        "count": 11777768
      },
      {
        "name": "image",
        "count": 10268383
      },
      {
        "name": "redirect",
        "count": 86656
      },
      // ...
    ],
    "top_countries": [
      {
        "name": "US",
        "count": 8437285
      },
      {
        "name": "",
        "count": 4870336
      },
      {
        "name": "WW",
        "count": 3208828
      },
      // ...
    ]
  },
  "meta": {
    "credits_charged": 4.5,
    "credits_remaining": 483.5,
    "request_id": "7f1a4da0-ae05-4890-89b8-f8503d33b697"
  }
}

POST/v1/domains/backlinks-list

Backlinks

The individual links, where the summary endpoint above gives you the totals. Source page, anchor text, whether the link is followed, the source's authority rank and when it was first and last seen.

Costs 9.3 credits per call, regardless of limit.

Required attributes

Name
target
Type
string
Description
A domain such as example.com, or one page such as example.com/pricing. A page target answers "who links to this article", which is the question worth asking before you rewrite it.

Optional attributes

Name
limit
Type
integer
Description
Links to return, 10 to 100. Default 50. Capped by your plan.
Name
per_domain
Type
boolean
Description
Return at most one link per linking domain. Default false. Turn it on when a single site links to you a thousand times and drowns out everything else.
Name
status
Type
string
Description
live, lost, new or all. Default live.

Response fields

Name
dofollow_count
Type
integer
Description
How many of the returned links pass authority.
Name
referring_domains
Type
integer
Description
Distinct domains among the returned links.
Name
backlinks[].anchor
Type
string
Description
The clickable text of the link, which is what tells you what the linking page thinks you are about.

Request

POST

/v1/domains/backlinks-list

curl -X POST https://suvjexogmfpvxjcktvuk.supabase.co/functions/v1/api/v1/domains/backlinks-list \
  -H "Authorization: Bearer $PENGU_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"target": "example.com", "limit": 50}'

Response

{
  "data": {
    "target": "example.com",
    "status": "live",
    "checked_at": "2026-09-20T09:50:22.004Z",
    "count": 50,
    "dofollow_count": 38,
    "referring_domains": 41,
    "backlinks": [
      {
        "from_domain": "industry-blog.com",
        "from_url": "https://industry-blog.com/best-tools-2026",
        "to_url": "https://example.com/pricing",
        "anchor": "Example pricing",
        "dofollow": true,
        "rank": 312,
        "page_title": "The 12 tools we actually pay for in 2026",
        "first_seen": "2026-02-14 09:11:02 +00:00",
        "last_seen": "2026-09-18 03:22:40 +00:00"
      }
    ]
  },
  "meta": {
    "credits_charged": 5.5,
    "credits_remaining": 2794.5,
    "request_id": "3f8b0c7e-1d42-4a99-8e06-2b1c7f5a9d30"
  }
}

POST/v1/domains/referring-domains

Referring domains

One row per linking domain instead of one per link. This is the number that matters for authority: a hundred links from one site are worth less than ten links from ten.

Costs 9.3 credits per call, regardless of limit.

Domains whose links are gone are dropped from the response. They describe history, not something you can act on today.

Required attributes

Name
domain
Type
string
Description
The domain to look up, bare: example.com.

Optional attributes

Name
limit
Type
integer
Description
Domains to return, 10 to 100. Default 50. Capped by your plan.

Response fields

Name
total_backlinks
Type
integer
Description
Links summed across the returned domains.
Name
referring_domains[].dofollow
Type
integer
Description
How many of that domain's links pass authority.
Name
referring_domains[].rank
Type
integer
Description
The linking domain's own authority rank. Sorted highest first.

Request

POST

/v1/domains/referring-domains

curl -X POST https://suvjexogmfpvxjcktvuk.supabase.co/functions/v1/api/v1/domains/referring-domains \
  -H "Authorization: Bearer $PENGU_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"domain": "example.com", "limit": 50}'

Response

{
  "data": {
    "domain": "example.com",
    "checked_at": "2026-09-20T09:52:10.663Z",
    "count": 50,
    "total_backlinks": 1284,
    "referring_domains": [
      {
        "domain": "industry-blog.com",
        "rank": 312,
        "backlinks": 14,
        "dofollow": 11,
        "referring_pages": 9,
        "first_seen": "2026-02-14 09:11:02 +00:00"
      }
    ]
  },
  "meta": {
    "credits_charged": 5.5,
    "credits_remaining": 2789,
    "request_id": "6c0d2a95-7b81-4e33-95af-1d84b2e60c57"
  }
}