Setting “checked” for a checkbox with jQuery

You can check or uncheck a checkbox element or a radio button using the .prop() method:

// Check #x
$( "#x" ).prop( "checked", true );

// Uncheck #x
$( "#x" ).prop( "checked", false );

f you’re working with just one element, you can always just access the underlying HTMLInputElement and modify its .checked property

$('.x')[0].checked = true;
$('.x')[0].checked = false;

jQuery 1.5.x and below

$('.x').attr('checked', true);
$('.x').attr('checked', false);

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