Find domains whose backlink profile overlaps with a target, useful for competitor discovery.

GET/v1/similar-domains5 creditsAPI key

Finds sites that tend to be linked from the same places as your target. It samples up to 30 domains that link to the target, looks at where each of those domains links out to, and ranks the destinations by how many of the sampled linkers point at them. Use it to discover competitors and peers you did not know about. Data comes from the pre-processed link graph snapshot (see Response format).

Request

Parameters

Parameter	Type	Required	Default	Description
`domain`	string	Yes	none	Domain to find peers for, for example `stripe.com`. No scheme or path. Must contain a dot.
`limit`	integer	No	`100`	Number of rows to return. Clamped to 1 to 100 (lower than most endpoints). A non-numeric value falls back to `100`.

This endpoint does not support offset. The maximum you can request is 100 rows.

Example

curl "https://api.rankparse.com/v1/similar-domains?domain=stripe.com&limit=20" \
  -H "X-API-Key: rp_your_key"

import requests

res = requests.get(
    "https://api.rankparse.com/v1/similar-domains",
    params={"domain": "stripe.com", "limit": 20},
    headers={"X-API-Key": "rp_your_key"},
    timeout=60,
)
res.raise_for_status()
body = res.json()
print(f"sampled {body['processed_linkers']} of {body['attempted_linkers']} linkers")
for row in body["data"]:
    print(row["similar_domain"], row["shared_linkers"])

const params = new URLSearchParams({ domain: "stripe.com", limit: "20" });

const res = await fetch(`https://api.rankparse.com/v1/similar-domains?${params}`, {
  headers: { "X-API-Key": "rp_your_key" },
});
if (!res.ok) throw new Error(`${res.status} ${await res.text()}`);
const { data, partial } = await res.json();
console.log(data, partial);

Response

{
  "domain": "stripe.com",
  "data": [
    { "similar_domain": "square.com", "shared_linkers": 19 },
    { "similar_domain": "paypal.com", "shared_linkers": 17 },
    { "similar_domain": "adyen.com", "shared_linkers": 11 }
  ],
  "total": 3,
  "limit": 20,
  "credits_used": 5,
  "credits_remaining": 995,
  "partial": false,
  "processed_linkers": 30,
  "attempted_linkers": 30,
  "budget_ms": 12000
}

Response fields

Top level:

Field	Type	Description
`domain`	string	The normalized (lowercased) domain you queried.
`data`	array	Similar domains sorted by `shared_linkers` descending. Empty when the domain has no linkers in the data.
`total`	integer	Number of rows returned in `data`.
`limit`	integer	The `limit` value you sent, echoed back as received.
`partial`	boolean	`true` when not every sampled linker was processed in time. Always present.
`processed_linkers`	integer	How many of the sampled linking domains were fully processed.
`attempted_linkers`	integer	How many linking domains were sampled (at most 30).
`budget_ms`	integer	The time budget for the fan-out, in milliseconds.
`credits_used`	integer	Always `5`.
`credits_remaining`	integer	Your balance after this call.

Each row in data:

Field	Type	Description
`similar_domain`	string	A domain that sampled linkers also link to. The target itself is excluded.
`shared_linkers`	integer	How many of the sampled linking domains link to this domain. It can never exceed `attempted_linkers`.

Behavior and limits

Sampled, not exhaustive: the analysis is based on at most 30 linking domains, and at most 500 outgoing destinations per linker. Treat shared_linkers as a relative signal, not a count of all shared linkers.
Partial results: the work fans out across linkers under a time budget. If the budget runs out, you get the results so far with partial: true and processed_linkers lower than attempted_linkers. Partial responses are billed normally but are not cached, so retrying later can return a fuller answer.
Credits: 5 per call, charged before the lookup. Server errors are refunded.
Caching: complete results are cached for 30 days per crawl release and per combination of domain and limit. A cache hit is billed the same as a fresh lookup.
Empty results: a domain with no linkers returns 200 with data: [], partial: false and zero counters, never 404.
Rate limit: 60 requests per minute per key. See Rate limiting.

Errors

HTTP	Code	When
400	`invalid_domain`	`domain` is missing or not a valid domain.
401	`invalid_api_key`	Missing, invalid or revoked API key.
402	`insufficient_credits`	Balance is lower than 5 credits.
402	`spend_cap_reached`	Your monthly spend cap is reached.
429	`rate_limited`	More than 60 requests in a minute.
503	`query_timeout`, `upstream_error`	Transient data store problem. Retry after the `Retry-After` header. Credits are refunded.