IP2Country

ip2country.php

<?php

$service_url = 'http://ipinfo.io/8.8.8.8/json';

$curl = curl_init($service_url);
curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
$curl_response = curl_exec($curl);
if ($curl_response === false) {
    $info = curl_getinfo($curl);
    curl_close($curl);
    die('error occured during curl exec. Additioanl info: ' . var_export($info));
}
curl_close($curl);
$decoded = json_decode($curl_response);
if (isset($decoded->response->status) && $decoded->response->status == 'ERROR') {
    die('error occured: ' . $decoded->response->errormessage);
}
echo 'response ok!';

echo '<pre>';
print_r($decoded->country);

If you just want the country details add /country to the http://ipinfo.io URL instead of /json. It'll be quicker, and save you from having to parse JSON. See http://ipinfo.io/developers for more details).