You can do
$('input[type=radio]').each(function(){ if($(this).is(':checked')){ alert('this button is checked'); } });
See the working example below:
$('button').click(function() { var counter = 1; $('input[type=radio]').each(function() { if ($(this).is(':checked')) { alert(' button ' + (counter) + ' is checked'); } counter++; }); });
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <input type=radio checked /> <input type=radio /> <input type=radio checked /> <button>check</button>
View on JSFiddle