'How can I check if a checkbox is checked?

I am building a mobile web app with jQuery Mobile and I want to check if a checkbox is checked. Here is my code.

<script type=text/javascript>
  function validate(){
    if (remember.checked == 1){
      alert("checked") ;
    } else {
      alert("You didn't check it! Let me check it for you.")
    }
  }
</script>

<input id="remember" name="remember" type="checkbox" onclick="validate()" />

But for some reason or another it doesn't execute it.

Please help !

----EDIT----- This is what I have for the moment.

<DIV data-role="content" data-theme="g">
    <DIV class=ui-grid-g-login>
        <FORM method=post action=[$=PROBE(266)/] data-theme="C">
            <P>~DATA_ERROR~</P>
            <div id="mail" data-role="fieldcontain">
                <label for="mail">Email:*</label>       
                <input id="mail" name="mail" type="email" />
            </div>
            <div id="pass" data-role="fieldcontain">
                <label for="pass">Paswoord:*</label>        
                <input id="pass" name="pass" type="password" />
            </div>
            <div id="remember" data-role="fieldcontain">
                <label for="remember">Onthoud mij</label>       
                <input id="remember" name="remember" type="checkbox" onclick="validate()" />
            </div>
            <P><INPUT class=btn name=submit value=Login type=submit  onclick="validate()"></P>  
        </FORM>
    </DIV>
</DIV><!-- /content -->

<script type=text/javascript>
function validate(){
    var remember = document.getElementById('remember');
    if (remember.checked){
        alert("checked") ;
    }else{
        alert("You didn't check it! Let me check it for you.")
    }
}
</script>

----EDIT--

Solved it, the problem was that the fieldcontain was also named 'remember'

Solution 1:^[1]

checked is a boolean property, so you can directly use it in an if condition

<script type="text/javascript">
    function validate() {
        if (document.getElementById('remember').checked) {
            alert("checked");
        } else {
            alert("You didn't check it! Let me check it for you.");
        }
    }
</script>

Solution 2:^[2]

Try this:

function validate() {
  var remember = document.getElementById("remember");
  if (remember.checked) {
    alert("checked");
  } else {
    alert("You didn't check it! Let me check it for you.");
  }
}

Your script doesn't know what the variable remember is. You need to get the element first using getElementById().

Solution 3:^[3]

This should allow you to check if element with id='remember' is 'checked'

if (document.getElementById('remember').is(':checked')

Solution 4:^[4]

If you are using this form for mobile app then you may use the required attribute html5. you dont want to use any java script validation for this. It should work

<input id="remember" name="remember" type="checkbox" required="required" />

Solution 5:^[5]

//HTML
<input type="checkbox" id="someID">

// JavaScript
const someCheckbox = document.getElementById('someID');

someCheckbox.addEventListener('change', e => {
  if(e.target.checked === true) {
    console.log("Checkbox is checked - boolean value: ", e.target.checked)
  }
if(e.target.checked === false) {
    console.log("Checkbox is not checked - boolean value: ", e.target.checked)
  }
});

know more

Solution 6:^[6]

use like this

<script type=text/javascript>
    function validate(){
        if (document.getElementById('remember').checked){
            alert("checked") ;
        } else {
            alert("You didn't check it! Let me check it for you.")
        }
    }
</script>

<input id="remember" name="remember" type="checkbox" onclick="validate()" />

Solution 7:^[7]

Use this below simple code: https://jsfiddle.net/Divyesh_Patel/v7a4h3kr/7/

<input type="checkbox" id="check">
<a href="#" onclick="check()">click</a>
<button onclick="check()">button</button>
<script>
  function check() {
    if (document.getElementById('check').checked) {
      alert("checked");
    } else {
      alert("Not checked.");
    }

  }
</script>

Solution 8:^[8]

This should work

function validate() {
    if ($('#remeber').is(':checked')) {
        alert("checked");
    } else {
        alert("You didn't check it! Let me check it for you.");
    }
}

Solution 9:^[9]

I am using this and it works for me with Jquery:

Jquery:

var checkbox = $('[name="remember"]');

if (checkbox.is(':checked'))
{
    console.log('The checkbox is checked');
}else
{
    console.log('The checkbox is not checked');
}

Is very simple, but work's.

Regards!

Solution 10:^[10]

if (document.getElementById('remember').checked) {
    alert("checked");
}
else {
    alert("You didn't check it! Let me check it for you.");
}

Solution 11:^[11]

remember is undefined … and the checked property is a boolean not a number.

function validate(){
    var remember = document.getElementById('remember');
    if (remember.checked){
        alert("checked") ;
    }else{
        alert("You didn't check it! Let me check it for you.")
    }
}

Solution 12:^[12]

The remember variable is undefined. so try this way:

function validate() {
  var remember = document.getElementById("remember");
  if (remember.checked) {
    alert("checked");
  } else {
    alert("You didn't check it! Let me check it for you.");
  }
}

Solution 13:^[13]

You can use this simple and effective code using pure JS and jQuery.

using validate function as onclick attr

function validate(el) {
    if (el.checked) {
        alert("checked")
    } else {
        alert("unchecked")
    }
}

<input id="remember" name="remember" type="checkbox" onclick="validate(this)" />

using pure JS

document.addEventListener("DOMContentLoaded", function(event) { 
    //using pure Js code
    let chk = document.getElementById("remember");
    if (chk.checked) {
        alert("checked")
    }else{
        alert("unchecked")
    }
})

<input id="remember" name="remember" type="checkbox"/>

using jQuery

$(document).ready(function () {
    //using jQuery code
    $('#remember').on('change', function (e) {
        if (e.currentTarget.checked) {
            alert("checked")
        } else {
            alert("unchecked")
        }
    })
})

<input id="remember" name="remember" type="checkbox"/>
<script src="https://code.jquery.com/jquery-3.6.0.min.js"></script>

Solution 14:^[14]

You can try this:

if ($('#remember').is(':checked')){
   alert('checked');
}else{
   alert('not checked')
}

Solution 15:^[15]

Use this below simple code: https://jsfiddle.net/Divyesh_Patel/v7a4h3kr/7/

<input type="checkbox" id="check">
<a href="#" onclick="check()">click</a>
<button onclick="check()">
button
</button>
<script>
  function check() {
    if (document.getElementById('check').checked) {
      alert("checked");
    } else {
      alert("You didn't check it! Let me check it for you.");
    }

  }
</script>

Solution 16:^[16]

Try This

<script type="text/javascript">
window.onload = function () {
    var input = document.querySelector('input[type=checkbox]');

    function check() {
        if (input.checked) {
            alert("checked");
        } else {
            alert("You didn't check it.");
        }
    }
    input.onchange = check;
    check();
}
</script>

Solution 17:^[17]

You can also use JQuery methods to accomplish this:

<script type="text/javascript">
if ($('#remember')[0].checked) 
{
 alert("checked");
}
</script>

Sources

This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.

Source: Stack Overflow

Solution	Source
Solution 1	Agostino
Solution 2	Newbyte
Solution 3	Matas Vaitkevicius
Solution 4	Luke
Solution 5	Crave
Solution 6	Douwe de Haan
Solution 7	Douwe de Haan
Solution 8	Douwe de Haan
Solution 9	Radames E. Hernandez
Solution 10	Douwe de Haan
Solution 11	Quentin
Solution 12	Muhammad Haris
Solution 13
Solution 14	Radames E. Hernandez
Solution 15	Douwe de Haan
Solution 16
Solution 17	Jesse

'How can I check if a checkbox is checked?

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