One of the ways to determine the age of the site is to use Wayback Machine. Just type your site’s URL and find the first record in results.

I wrote the function to automate this operation and included it to my SEO helper for CodeIgniter.

The following example shows how to use it:

$this->load->helper('seo');
$age = domain_age('codeigniter.com');
if ($age !== '-1')
{
  echo "Year: $age[year], month: $age[month], day: $age[day]";
}
else
{
  echo 'No records found!';
}

As you see this is very easy.

Download SEO helper version 1.2 for CodeIgniter