how to calculate google backlinks using php

Question

i want to create my own tool for back-links calculation using PHP. is there any api to fetech the data for back links

Answer 1

The full implementation in PHP would look something like this:

<?php
$domain = "example.com"; // Enter your domain here.

$url = "http://ajax.googleapis.com/ajax/services/search/web?v=1.0&rsz=large&"
    . "q=link:".$domain;

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_REFERER, $domain);
$body = curl_exec($ch);
curl_close($ch);

$json = json_decode($body);
$urls = array();
foreach($json->responseData->results as $result) // Loop through the objects in the result
    $urls[] = $result->unescapedUrl;             // and add the URL to the array.
?>

Basically you edit the domain variable at the top and it will fill the $urls array with unescaped URLs linking to the domain.

EDIT: I've edited the link to return 8 results. For more, you'll have to parse the pages and loop through them with the start parameter. See the Class Reference for more information.

Answer 2

Run a Google search with the URL prefixed by link: - for instance, link:www.mydomain.com.

While Google does provide a more specific backlink overview in their Webmaster Tools area (more info), I'm not sure they provide an external API for it.