Compatible Browsers:
Example: View Code Demo
<html>
<head>
<title>Check & Uncheck Check Boxes Javascript Code Snippet</title>
<script>
<!-- Begin Check & Uncheck Check Boxes from https://snapbuilder.com Free Public Codes Library
// Free to use as long as the credit lines remain in place
var checkflag = "false";
function check(field) {
if (checkflag == "false") {
for (i = 0; i < field.length; i++) {
field[i].checked = true;}
checkflag = "true";
return "Uncheck All"; }
else {
for (i = 0; i < field.length; i++) {
field[i].checked = false; }
checkflag = "false";
return "Check All"; }
}
// End -->
</script>
</head>
<body>
<center>
<form name="myform" action="" method="post">
<table>
<tr>
<td><b>Your Favorite Scripts & Languages</b><br />
<input type="checkbox" name="list" value="1">jQuery<br>
<input type="checkbox" name="list" value="2">Javascript<br />
<input type="checkbox" name="list" value="3">PHP<br />
<input type="checkbox" name="list" value="4">HTML<br />
<input type="checkbox" name="list" value="5">SQL<br /><br />
<input type="button" value="Check All" onClick="this.value=check(this.form.list)"></td>
</tr>
</table>
</form>
</center>
</body>
</html>