MIFARE Classic 1K Access Bits Calculator is a simple html/javascript calculator for the Mifare Classic 1K access bits.
Widget was based on this code The information on access bits is taken from MF1S503x from NXP Seiconductors.
To use, simply clone the code and add this to a page:
<script type='text/javascript'>
wWidth = "800px";
wHeight = "195px";
document.write('<div id="mifareWidget"></div>');
document.write('<scr'+'ipt type="text/JavaScript" src="mifareWidget/WidgetCreate.js"></scr'+'ipt>');
</script>