Associated Domain Finder

GEThttps://api.deepinfo.com/v1/discovery/associated-domain-finder

Finds domains associated with a domain: same registrant email, organization or phone, same name servers, IP, mail servers or SSL organization. Choose the association type(s); strict requires every association to match.

Example

Request

curl

curl 'https://api.deepinfo.com/v1/discovery/associated-domain-finder?domain=deepinfo.com&page_size=25' \
  -H 'apikey: YOUR_API_KEY' \
  -H 'Accept: application/json'

Python

import requests

url = "https://api.deepinfo.com/v1/discovery/associated-domain-finder"

params = {
    "domain": "deepinfo.com",
    "page_size": "25"
}

headers = {
    "apikey": "YOUR_API_KEY",
    "Accept": "application/json"
}

response = requests.get(url, params=params, headers=headers)
response.raise_for_status()
print(response.json())

JavaScript

const url = "https://api.deepinfo.com/v1/discovery/associated-domain-finder?domain=deepinfo.com&page_size=25";

const response = await fetch(url, {
  method: "GET",
  headers: {
    "apikey": "YOUR_API_KEY",
    "Accept": "application/json"
  },
});

const data = await response.json();
console.log(data);

package main

import (
	"fmt"
	"io"
	"net/http"
)

func main() {
	req, err := http.NewRequest("GET", "https://api.deepinfo.com/v1/discovery/associated-domain-finder?domain=deepinfo.com&page_size=25", nil)
	if err != nil {
		panic(err)
	}
	req.Header.Set("apikey", "YOUR_API_KEY")
	req.Header.Set("Accept", "application/json")

	res, err := http.DefaultClient.Do(req)
	if err != nil {
		panic(err)
	}
	defer res.Body.Close()

	body, err := io.ReadAll(res.Body)
	if err != nil {
		panic(err)
	}
	fmt.Println(string(body))
}

Java

import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;

public class Main {
    public static void main(String[] args) throws Exception {
        HttpRequest request = HttpRequest.newBuilder()
            .uri(URI.create("https://api.deepinfo.com/v1/discovery/associated-domain-finder?domain=deepinfo.com&page_size=25"))
            .header("apikey", "YOUR_API_KEY")
            .header("Accept", "application/json")
            .GET()
            .build();

        HttpResponse<String> response = HttpClient.newHttpClient()
            .send(request, HttpResponse.BodyHandlers.ofString());

        System.out.println(response.body());
    }
}

using System;
using System.Net.Http;

using var client = new HttpClient();

var request = new HttpRequestMessage(HttpMethod.Get, "https://api.deepinfo.com/v1/discovery/associated-domain-finder?domain=deepinfo.com&page_size=25");
request.Headers.Add("apikey", "YOUR_API_KEY");
request.Headers.Add("Accept", "application/json");

using var response = await client.SendAsync(request);
Console.WriteLine(await response.Content.ReadAsStringAsync());

PHP

<?php

$curl = curl_init();

curl_setopt_array($curl, [
    CURLOPT_URL => 'https://api.deepinfo.com/v1/discovery/associated-domain-finder?domain=deepinfo.com&page_size=25',
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_HTTPHEADER => [
        'apikey: YOUR_API_KEY',
        'Accept: application/json',
    ],
]);

$response = curl_exec($curl);

if ($response === false) {
    throw new RuntimeException(curl_error($curl));
}

echo $response . PHP_EOL;

Ruby

require 'net/http'
require 'uri'

uri = URI('https://api.deepinfo.com/v1/discovery/associated-domain-finder?domain=deepinfo.com&page_size=25')

request = Net::HTTP::Get.new(uri)
request['apikey'] = 'YOUR_API_KEY'
request['Accept'] = 'application/json'

response = Net::HTTP.start(uri.hostname, uri.port, use_ssl: uri.scheme == 'https') do |http|
  http.request(request)
end

puts response.body

Response

200 OK · application/json

Response Body

{
  "page": 1,
  "page_size": 25,
  "result_count": 0,
  "results": [],
  "domain": "deepinfo.com",
  "requested_association_parameters": [
    "whois_registrant_email",
    "whois_registrant_email_apex_normalized"
  ],
  "applied_association_parameters": []
}

Content-Type: application/json
deepinfo-request-id: 5f0c6a8e-1b2d-4c3e-9f4a-7b8c9d0e1f2a

Request

curl

curl 'https://api.deepinfo.com/v1/discovery/associated-domain-finder?export=notabool&domain=deepinfo.com' \
  -H 'apikey: YOUR_API_KEY' \
  -H 'Accept: application/json'

Python

import requests

url = "https://api.deepinfo.com/v1/discovery/associated-domain-finder"

params = {
    "export": "notabool",
    "domain": "deepinfo.com"
}

headers = {
    "apikey": "YOUR_API_KEY",
    "Accept": "application/json"
}

response = requests.get(url, params=params, headers=headers)
response.raise_for_status()
print(response.json())

JavaScript

const url = "https://api.deepinfo.com/v1/discovery/associated-domain-finder?export=notabool&domain=deepinfo.com";

const response = await fetch(url, {
  method: "GET",
  headers: {
    "apikey": "YOUR_API_KEY",
    "Accept": "application/json"
  },
});

const data = await response.json();
console.log(data);

package main

import (
	"fmt"
	"io"
	"net/http"
)

func main() {
	req, err := http.NewRequest("GET", "https://api.deepinfo.com/v1/discovery/associated-domain-finder?export=notabool&domain=deepinfo.com", nil)
	if err != nil {
		panic(err)
	}
	req.Header.Set("apikey", "YOUR_API_KEY")
	req.Header.Set("Accept", "application/json")

	res, err := http.DefaultClient.Do(req)
	if err != nil {
		panic(err)
	}
	defer res.Body.Close()

	body, err := io.ReadAll(res.Body)
	if err != nil {
		panic(err)
	}
	fmt.Println(string(body))
}

Java

import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;

public class Main {
    public static void main(String[] args) throws Exception {
        HttpRequest request = HttpRequest.newBuilder()
            .uri(URI.create("https://api.deepinfo.com/v1/discovery/associated-domain-finder?export=notabool&domain=deepinfo.com"))
            .header("apikey", "YOUR_API_KEY")
            .header("Accept", "application/json")
            .GET()
            .build();

        HttpResponse<String> response = HttpClient.newHttpClient()
            .send(request, HttpResponse.BodyHandlers.ofString());

        System.out.println(response.body());
    }
}

using System;
using System.Net.Http;

using var client = new HttpClient();

var request = new HttpRequestMessage(HttpMethod.Get, "https://api.deepinfo.com/v1/discovery/associated-domain-finder?export=notabool&domain=deepinfo.com");
request.Headers.Add("apikey", "YOUR_API_KEY");
request.Headers.Add("Accept", "application/json");

using var response = await client.SendAsync(request);
Console.WriteLine(await response.Content.ReadAsStringAsync());

PHP

<?php

$curl = curl_init();

curl_setopt_array($curl, [
    CURLOPT_URL => 'https://api.deepinfo.com/v1/discovery/associated-domain-finder?export=notabool&domain=deepinfo.com',
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_HTTPHEADER => [
        'apikey: YOUR_API_KEY',
        'Accept: application/json',
    ],
]);

$response = curl_exec($curl);

if ($response === false) {
    throw new RuntimeException(curl_error($curl));
}

echo $response . PHP_EOL;

Ruby

require 'net/http'
require 'uri'

uri = URI('https://api.deepinfo.com/v1/discovery/associated-domain-finder?export=notabool&domain=deepinfo.com')

request = Net::HTTP::Get.new(uri)
request['apikey'] = 'YOUR_API_KEY'
request['Accept'] = 'application/json'

response = Net::HTTP.start(uri.hostname, uri.port, use_ssl: uri.scheme == 'https') do |http|
  http.request(request)
end

puts response.body

Response

400 Bad Request · application/json

Response Body

{
  "code": 10400,
  "parameters": [
    {
      "param": "export",
      "details": [
        "Must be a valid boolean."
      ]
    }
  ],
  "solution": "https://docs.deepinfo.com/reference/"
}

Content-Type: application/json
deepinfo-request-id: 5f0c6a8e-1b2d-4c3e-9f4a-7b8c9d0e1f2a

Authentication

Send your API key in the apikey request header.

Query Parameters

Parameter	Required	Description
`domain`	Required	Example`deepinfo.com`
`page_size`	Optional	Min `25`, max `100`. Default `100`. Example`25`
`ordering`	Optional
`export`	Optional	Default `false`.
`export_format`	Optional	One of: `json`, `csv`.
`export_scope`	Optional	One of: `basic`, `default`, `extended`.
`association`	Optional
`strict`	Optional	Default `false`.
`include_subdomains`	Optional	Default `false`.
`page`	Optional	Min `1`, max `400`. Default `1`. Example`1`

Response Fields

Field	Type	Description
`page`	integer
`page_size`	integer
`result_count`	integer
`results`	array of object
`domain`	string
`requested_association_parameters`	array of string
`applied_association_parameters`	array of string
`results[].punycode`	string
`results[].unicode`	string
`results[].is_idn`	boolean
`results[].subdomain`	object
`results[].subdomain_last`	object
`results[].subdomain_root`	object
`results[].name`	object
`results[].domain`	object
`results[].type`	integer
`results[].subdomain_level_count`	integer
`results[].dns`	object
`results[].dns_last_change_date`	string	date-time
`results[].ip_history`	array of string
`results[].ssl`	object
`results[].ssl_last_change_date`	string	date-time
`results[].webdata`	object

Paginated. See Getting Started → Pagination.

Response Schema

Inferred from examples Built from the saved 2xx example response: the fields it contains, with the types seen there. It is not a contract.

Field	Type	Example
`page`	number	`1`
`page_size`	number	`25`
`result_count`	number	`0`
`results`	array
`domain`	string	`"deepinfo.com"`
`requested_association_parameters`	array<string>	`"whois_registrant_email"`
`applied_association_parameters`	array

Examples

Saved examples from the Deepinfo API. Selecting one loads it into the request and response panels.

Worked Examples

Worked examples of this endpoint, each on its own page with the exact request and the response it returns.

Domains Associated With a DomainEvery association type for paypal.com: 3,334 related domains, found through registrant organization, name servers, mail servers and certificate.
Every Association Must Match (Strict)With strict=true, every applied association must match: 29 domains for paypal.com instead of 3,334.
Same Registrant OrganizationThe domains registered to the same organization as paypal.com (“paypal inc.”): 3,187.

See all examples

Reference updated September 27, 2026