jquery is checked

//using plane javascript 
if(document.getElementById('on_or_off_checkbox').checked) {
    //I am checked
} 

//using jQuery
if($('#on_or_off_checkbox').is(':checked')){
    //I am checked
}$( "SELECTOR" ).attr( "checked" )  // Returns ‘true’ if present on the element, returns undefined if not present
$( "SELECTOR" ).prop( "checked" ) // Returns true if checked, false if unchecked.
$( "SELECTOR" ).is( ":checked" ) // Returns true if checked, false if unchecked.if ($('#check_id').is(":checked"))
{
  // it is checked
}$("checkbox").is(":checked")if ($('#grepperRocks').is(':checked')) {
	// this checkbox is checked
}if ($('[name="your_input_checkbox_name"]').is(":checked"))
{
  // it is checked
} else {
  // it isn't checked	
}