Redirects API

API Credit Usage

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Introduction

API endpoint that allows you to get access to live and historical redirects for a website.

The general access method is as follows -
https://api.builtwith.com/redirect1/api.[xml|json]?KEY=00000000-0000-0000-0000-000000000000&LOOKUP=[DOMAIN NAME]

Authentication

You must provide your API key in each lookup. Our endpoints are HTTPS only, providing key encryption. Never expose your API key.

Your API Key is
00000000-0000-0000-0000-000000000000

Get Domain Example

XML Get Single Domain
https://api.builtwith.com/redirect1/api.xml?KEY=00000000-0000-0000-0000-000000000000&LOOKUP=hotelscombined.com

JSON Get Single Domain
https://api.builtwith.com/redirect1/api.json?KEY=00000000-0000-0000-0000-000000000000&LOOKUP=builtwith.com

Code Examples

Here are implementation examples in different programming languages for making API requests:

var client = new HttpClient();
var request = new HttpRequestMessage
{
    Method = HttpMethod.Get,
    RequestUri = new Uri("https://api.builtwith.com/redirect1/api.json" +
                        "?KEY=00000000-0000-0000-0000-000000000000&LOOKUP=wayfair.com"),
};
using (var response = await client.SendAsync(request))
{
    response.EnsureSuccessStatusCode();
    var body = await response.Content.ReadAsStringAsync();
    Console.WriteLine(body);
}
import requests
url = "https://api.builtwith.com/redirect1/api.json"
params = {
    'KEY': '00000000-0000-0000-0000-000000000000',
    'LOOKUP': 'wayfair.com'
}
response = requests.get(url, params=params)
print(response.json())
<?php
$url = "https://api.builtwith.com/redirect1/api.json";
$params = array(
    'KEY' => '00000000-0000-0000-0000-000000000000',
    'LOOKUP' => 'wayfair.com'
);
$url_with_params = $url . '?' . http_build_query($params);
$response = file_get_contents($url_with_params);
$data = json_decode($response, true);
print_r($data);
?>
const https = require('https');
const url = 'https://api.builtwith.com/redirect1/api.json?KEY=00000000-0000-0000-0000-000000000000&LOOKUP=wayfair.com';
https.get(url, (res) => {
    let data = '';
    res.on('data', (chunk) => {
        data += chunk;
    });
    res.on('end', () => {
        console.log(JSON.parse(data));
    });
}).on('error', (err) => {
    console.log('Error: ' + err.message);
});
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
public class BuiltWithAPI {
    public static void main(String[] args) throws Exception {
        String url = "https://api.builtwith.com/redirect1/api.json" +
                    "?KEY=00000000-0000-0000-0000-000000000000&LOOKUP=wayfair.com";
        URL obj = new URL(url);
        HttpURLConnection con = (HttpURLConnection) obj.openConnection();
        con.setRequestMethod("GET");
        BufferedReader in = new BufferedReader(
            new InputStreamReader(con.getInputStream()));
        String inputLine;
        StringBuffer response = new StringBuffer();
        while ((inputLine = in.readLine()) != null) {
            response.append(inputLine);
        }
        in.close();
        System.out.println(response.toString());
    }
}
require 'net/http'
require 'uri'
require 'json'
uri = URI('https://api.builtwith.com/redirect1/api.json')
uri.query = URI.encode_www_form({
    'KEY' => '00000000-0000-0000-0000-000000000000',
    'LOOKUP' => 'wayfair.com'
})
response = Net::HTTP.get_response(uri)
data = JSON.parse(response.body)
puts data
package main
import (
    "fmt"
    "io/ioutil"
    "net/http"
)
func main() {
    url := "https://api.builtwith.com/redirect1/api.json?KEY=00000000-0000-0000-0000-000000000000&LOOKUP=wayfair.com"
    resp, err := http.Get(url)
    if err != nil {
        panic(err)
    }
    defer resp.Body.Close()
    body, err := ioutil.ReadAll(resp.Body)
    if err != nil {
        panic(err)
    }
    fmt.Println(string(body))
}
curl -X GET "https://api.builtwith.com/redirect1/api.json?KEY=00000000-0000-0000-0000-000000000000&LOOKUP=wayfair.com"
Reference
Parameters
The following GET parameters can be supplied for lookups
NameExamplesRequired
KEY00000000-0000-0000-0000-000000000000
This is your key, use this for lookups.
Yes
LOOKUPcnn.com
ycombinator.com
Only root domains work with the Redirect API (not internal pages or subdomains)
Yes
Responses
Redirect is the top level response that identifies the lookup.
NameExampleDescription
Lookuphotelscombined.comThe domain that was looked up.
InboundSee belowThe list of sites that direct towards the Lookup.
OutboundSee belowThe list of sites that Lookup has redirected to.
Direction
This is the domains that are either Inbound or Outbound to the Lookup with their timings.
NameExampleDescription
DomainThe domain of the redirectA domain that either redirects from or to the Lookup (depending on if it's in the Inbound or Outbound group).
FirstDetected2018-02-01The date we first detected the redirect.
LastDetected2025-06-02The date we last detected the redirect.
Special Domains

We maintain two lists of use for you when looking up domains. Ignore lists and BuiltWith Suffix lists.

Ignore List
This is our own internal list of domains we do not index. They are either blocked, contains too many misleading technologies or too many subdomains with user generated content.

BuiltWith Suffix List
This is based on the Public Suffix List but includes many additional entries for companies with subdomains that should be considered top level domains. This list provides us with better visibility for internal websites for example it brings northernbeaches.nsw.gov.au to the top level over nsw.gov.au.

Ignore Domains (XML, JSON or TXT)
https://api.builtwith.com/ignoresv1/api.json
Suffix Domains (XML, JSON or TXT)
https://api.builtwith.com/suffixv1/api.json
Error Codes

Note error messages in this format cannot be guaranteed, your implementation should also consider non-200 response codes as errors. The Lookup property will be null (json) or not provided (xml) if the error is server related. View all potential well-formed error codes.

Terms of Use

Our standard terms cover the use all of our APIs.

In general, you can use the API to enhance your product in many ways. The only limitation is you cannot resell the data as-is or provide duplicate functionality to builtwith.com and its associated services.