<form name="form1" method="post" action="">
<p>TTL :
<label for="tmp"></label>
<input type="text" name="tmp" id="tmp">
<?php
echo "<select name='tgl'>";
echo "<option selected='selected'>Tanggal</option>";
for($a=1; $a<=31; $a+=1)
{
echo"<option value=$a> $a </option>";
}
echo "</select>";
echo "<select name='bln'>";
echo "<option selected='selected'>Bulan</option>";
$bulan=array("Januari","Februari","Maret","April","Mei","Juni","Juli","Agustus","September","Oktober","November","Desember");
$jlh_bln=count($bulan);
for($c=0; $c<$jlh_bln; $c+=1)
{
echo"<option value=$bulan[$c]> $bulan[$c] </option>";
}
echo "</select>";
$now=date('Y');
$tahun=$_POST['tahun'];
echo "<select name='tahun'>";
echo "<option selected='selected'>Tahun</option>";
for ($a=1990;$a<=$now;$a++)
{
echo "<option value='$a'>$a</option>";
}
echo "</select>";
?>
</p>
<p>UMUR :
<label for="umr"></label>
<input type="text" name="umr" id="umr" value="<?php echo ($umur=$now-$tahun);?>" readonly>
</p>
</form>