Backlinks API documentation

Quick start

Base URL: https://backlinks.uk.app/api/v1. Registe-se, create an API key in your account and send your first request:

curl -H "X-API-Key: YOUR_KEY" "https://backlinks.uk.app/api/v1/overview?q=github.com"

Data: an index of 181M domains and 2.7B links, refreshed roughly monthly. Domains are normalised automatically: case and the www. prefix don't matter.

Authentication

Every request except /v1/health must include the API key in a header:

X-API-Key: bl_live_…

Also accepted: Authorization: Bearer …. Passing the key in URL parameters is not allowed: it would end up in logs and browser history.

Credits & limits

Each call costs 1–3 credits depending on the endpoint, regardless of how many rows it returns (up to 1,000). Your plan's credits for the current month are used first, then the prepaid balance. If a request fails on our side, the credits are returned. Plans & packs

Your remaining credits are also in the _credits field of every response and in /v1/account (free).

Response format and errors

Every response has an ok field. Lists include rows, total, page and per. On error: ok = false, error — a message, code — a machine-readable code.

{ "ok": true, "domain": "github.com", "summary": { "dr": 83, "backlinks": 826422352, "ref_domains": 1233241, … },
  "_credits": { "cost": 1, "plan_remaining": 1999, "balance": 0, "available": 1999, "cached": false } }

{ "ok": false, "code": "insufficient_credits", "error": "Not enough credits: this call costs 2, you have 1. …" }

Endpoints

All endpoints are GET /api/v1/{name}. Pagination: page (from 1) and per (10–1000). Sorting: sort + order=asc|desc.

* — required parameter

Code examples

# curl — top referring domains by links
curl -H "X-API-Key: $KEY" "https://backlinks.uk.app/api/v1/refdomains?q=github.com&sort=links&per=20"

# curl — DR for a list of domains (POST, up to 2000)
curl -H "X-API-Key: $KEY" --data-binary $'github.com\nmoz.com\nnytimes.com' "https://backlinks.uk.app/api/v1/bulk_dr"

# Python
import os, requests
r = requests.get("https://backlinks.uk.app/api/v1/backlinks",
                 params={"q": "github.com", "per": 100, "follow": 1},
                 headers={"X-API-Key": os.environ["KEY"]}, timeout=30)
r.raise_for_status()
data = r.json()
for row in data["rows"]:
    print(row)
print("credits left:", data["_credits"]["available"])

// Node.js 18+ (on the server — not in the browser)
const res = await fetch("https://backlinks.uk.app/api/v1/overview?q=github.com", { headers: { "X-API-Key": process.env.KEY } });
const d = await res.json();
if (!d.ok) throw new Error(d.error);
console.log(d.summary.dr, d.summary.ref_domains);

// PHP
$ch = curl_init('https://backlinks.uk.app/api/v1/anchors?q=github.com&per=50');
curl_setopt_array($ch, [CURLOPT_RETURNTRANSFER => true, CURLOPT_HTTPHEADER => ['X-API-Key: ' . getenv('KEY')]]);
$d = json_decode(curl_exec($ch), true);
foreach ($d['rows'] as $a) echo $a['anchor'], PHP_EOL;

Try it

You can create a key in your account. The request goes straight from your browser. The key is not stored anywhere and is gone after a page reload. Requests from the console spend credits like any other.