Write below code with name "check.html".
<form action=proses-domain.php method=post>
<table>
<tr>
<td>Periksa Domain</td>
<td> : <input type=text name=domain></td>
<td>
<select name="suffix">
<option value=".com">.com</option>
<option value=".net">.net</option>
<option value=".org">.org</option>
<option value=".biz">.biz</option>
<option value=".info">.info</option>
<option value=".mobi">.mobi</option>
<option value=".ws">.ws</option>
<option value=".co.id">.co.id</option>
<option value=".or.id">.or.id</option>
<option value=".go.id">.go.id</option>
<option value=".sch.id">.sch.id</option>
<option value=".ac.id">.ac.id</option>
<option value=".mil.id">.mil.id</option>
<option value=".web.id">.web.id</option>
<option value=".tv">.tv</option>
<option value=".cn">.cn</option>
<option value=".cc">.cc</option>
</select>
</td>
<tr>
<td align=right colspan=3>
<input type=submit name=proses value="Periksa Sekarang!"></td>
</tr>
</tr>
</table>
</form>
Write below php code with name "process.php".
<?php
if($_POST[proses]){
$nama_domain = "$_POST[domain]"."$_POST[suffix]";
$arrHost = @gethostbynamel("$nama_domain");
if(empty($arrHost)){
echo "Domain $nama_domain Available";
}else{
echo "Domain $nama_domain Not available";
}
}
?>