In this article I will explain with an example, how to check if a RadioButton or RadioGroup (i.e. set of RadioButtons) is checked (selected) or not checked (not selected) using jQuery.
When the RadioButton is clicked based on whether it is checked (selected) or unchecked (unselected), the HTML DIV will be shown or hidden using jQuery.
Check if a RadioButton (RadioGroup) is checked or not using jQuery
The HTML Markup consists of two RadioButtons (one for Yes and other for No) and an HTML DIV consisting of a TextBox. Each RadioButton has been assigned a jQuery OnClick event handler.
Note: The RadioButtons must be set with exact same name attribute values in order to make them mutually exclusive.
When the RadioButton is clicked, based on Yes RadioButton is checked (selected) or unchecked (unselected), the HTML DIV with TextBox is shown or hidden.
<script type="text/javascript" src=""></script>
<script type="text/javascript">
    $(function () {
        $("input[name='chkPassPort']").click(function () {
            if ($("#chkYes").is(":checked")) {
            } else {
<span>Do you have Passport?</span>
<label for="chkYes">
    <input type="radio" id="chkYes" name="chkPassPort" />
<label for="chkNo">
    <input type="radio" id="chkNo" name="chkPassPort" />
<hr />
<div id="dvPassport" style="display: none">
    Passport Number:
    <input type="text" id="txtPassportNumber" />
Check if a RadioButton (RadioGroup) is checked or not using jQuery
Browser Compatibility

The above code has been tested in the following browsers.

Internet Explorer  FireFox  Chrome  Safari  Opera 

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