Internet Marketing with a Helmet.

Using DKI (Dynamic Keyword Insertion) is helpful to increase CTR on your landing pages.

Normally this is a fairly simple task. If you’re using Prosper202 and you’ve got your campaign and tracking setup correctly, 202 should pass your keyword in the URL to your landing page. So you’re landing page URL will look something like this:

http://mydomain.com/landingpage.php?t202kw=walmart.com

To “grab” this keyword and use it in your page, you simply do something like this:

<?php
$target = $_GET['t202kw'];
?>

<h1>Welcome <?php echo $target; ?> Visitors!!!</h1>

(For more about this, check out I don’t get GET’s!)

The Problem

Depending on what target your bidding on in PPV, many times these keywords aren’t “perfect” domains. If So you might end up with something like this:

Welcome ./shoppingcart.walmart.com Visitors!!!

That’s lame.

This Function

…basically trims the target to its root domain and makes it as pretty as possible so you don’t look like a tool to your visitors. I’ve seen a few bits of code floating around that promise to do this for you, but they’ve all done a poor job (a.k.a. suck). Most of them don’t trim subdomains and many of them don’t handle pre-pended and trailing slashes. This one does.

Here’s an example of what this function can do:

http://CTRtard.com = ctrtard.com
https://CtrTard.com = ctrtard.com
http://www.ctrtard.com = ctrtard.com
https://www.ctrtard.com/ = ctrtard.com
/ctrtard.com = ctrtard.com
./ctrtard.com = ctrtard.com
ctrtard.ly = ctrtard.ly
ctrtard.org = ctrtard.org
ww.ctrtard.org = ctrtard.org
//ctrtard.com = ctrtard.com
money.ctrtard.com = ctrtard.com
/ctrtard.com/ = ctrtard.com
//something.ctrtard.com/ = ctrtard.com
//something.ctrtard.com/?morestuff = ctrtard.com

The Code

<?php
function trim_url_to_root_domain($target) {
/** Trim Url to Root Domain
* by ctrtard.com 8/1/2011
*
* This function is mainly useful for PPV. You can pass it a URL (target) and it
* will trim it down to the root domain.  Unlike most other examples I've found,
* It handles subdomains and squirrely, or malformed URLs like "//something.domain.com"
* The result is a nice looking domain for dynamic keyword insertion into your
* landing pages.
*
* Usage:
* echo trim_url_to_root_domain("http://mytarget.com");
* or
* echo ucfirst (trim_url_to_root_domain("http://mytarget.com")); // uppercase first letter
*
*/
    // trim http, https, and //
    $target = str_replace("http:", "", $target);
    $target = str_replace("https:", "", $target);
    $target = str_replace("//", "", $target);

    // check for dots
    $dots = substr_count($target, '.');
    if ($dots > 1) { // if there are more than 1 dots, we need to remove subdomain
        $first_dot = strpos ($target, ".");
        $target = substr($target, $first_dot+1, strlen($target));
    }

    // find the last slash, this should be the slash just before directory info
    $last_slash = strripos($target, "/");
    if ($last_slash > 0 ) {
        $target = substr($target, 0, $last_slash);
    }

    // find last slash one more time, to handle targets like /domain.com
    $last_slash = strripos($target, "/");
    if ($last_slash !== FALSE ) {
        $target = substr($target, 1, strlen($target));
    }

    // normalize target so it's all lower case
    $target = strtolower($target);

    return $target;
}
?>

Usage

I hope most of you know how to use this, but just in case…. Copy & paste this function at the bottom of your LP. Your LP should have a .php extension. To grab the keyword from 202, use the example I gave above. Then, instead of this:

<h1>Welcome <?php echo $target; ?> Visitors!!!</h1>

do this:

<h1>Welcome <?php echo trim_url_to_root_domain($target); ?> Visitors!!!</h1>

That’s it! You can also capitalize the first letter of the domain using PHP’s ucfirst function. Check out the comments in the function for how to do this.

You Break it You Buy It

So far this function has worked pretty well for me, but nobody’s perfect.  If you happen to find a target that doesn’t get trimmed correctly, please post in the comments below and I’ll see what I can do to fix it.

But Wait, There’s More!

I did a guest post on PPV Playbook Blog today called “Killer Buttons To Squeeze More CTR From Your Landing Pages“.  Check it out!

Related posts:

1. Split Testing and Landing Page Rotation Script for PPV
2. Tracking202 Missing PPV Icons Fix
3. Pimp Your Prosper with Subid Injection Buttons
4. I don’t get GETs!
5. Split Testing and Rotating Offers in Tracking202