How can I change the default width of a Twitter Bootstrap modal box?

Answer 1

Try something like the following (see live jsfiddle example here: http://jsfiddle.net/periklis/hEThw/1/)

<a class="btn" onclick = "$('#myModal').modal('show');$('#myModal').css('width', '100px').css('margin-left','auto').css('margin-right','auto');" ref="#myModal" >Launch Modal</a>
<div class="modal" id="myModal" style = "display:none">
  <div class="modal-header">
    <a class="close" data-dismiss="modal">×</a>
    <h3>Modal header</h3>
  </div>
  <div class="modal-body">
    <p>One fine body…</p>
  </div>
  <div class="modal-footer">
    <a href="#" class="btn">Close</a>
    <a href="#" class="btn btn-primary">Save changes</a>
  </div>
</div>​

Answer 2

If you want to make it responsive with just CSS, use this:

.modal.large {
    width: 80%; /* respsonsive width */
    margin-left:-40%; /* width/2) */ 
}

Note 1: I used a .large class, you could also do this on the normal .modal

Note 2: In Bootstrap 3 the negative margin-left may not be needed anymore (not confirmed personally)

/*Bootstrap 3*/
.modal.large {
     width: 80%;
}

Note 3: In Bootstrap 3 and 4, there is a modal-lg class. So this may be sufficient, but if you want to make it responsive, you still need the fix I provided for Bootstrap 3.

In some application fixed modals are used, in that case you could try width:80%; left:10%; (formula: left = 100 - width / 2)

Answer 3

Achieved expected result using,

.modal-dialog {
    width: 41% !important;
}

Answer 4

For Bootstrap 3 here's how to do it.

Add a modal-wide style to your HTML markup (as adapted from the example in the Bootstrap 3 docs)

<div class="modal fade modal-wide" id="myModal" tabindex="-1" role="dialog" aria-labelledby="myModalLabel" aria-hidden="true">
  <div class="modal-dialog">
    <div class="modal-content">
      <div class="modal-header">
        <button type="button" class="close" data-dismiss="modal" aria-hidden="true">&times;</button>
        <h4 id="myModalLabel" class="modal-title">Modal title</h4>
      </div>
      <div class="modal-body">
        <p>One fine body&hellip;</p>
      </div>
      <div class="modal-footer">
        <button type="button" class="btn btn-default" data-dismiss="modal">Close</button>
        <button type="button" class="btn btn-primary">Save changes</button>
      </div>
    </div><!-- /.modal-content -->
  </div><!-- /.modal-dialog -->
</div><!-- /.modal -->

and add the following CSS

.modal-wide .modal-dialog {
  width: 80%; /* or whatever you wish */
}

There is no need to override margin-left in Bootstrap 3 to get this to be centered now.

Answer 5

Preserve the responsive design, set the width to what you desire.

.modal-content {
  margin-left: auto;
  margin-right: auto;
  max-width: 360px;
}

Keep it simple.

Answer 6

Rather than using percentages to make the modal responsive, I find there can be more control taken from using the columns and other responsive elements already built into bootstrap.

---

To make the modal responsive/the size of any amount of columns:

1) Add an extra div around the modal-dialog div with a class of .container -

<div class="container">
    <div class="modal-dialog">
    </div>
</div>

2) Add a little CSS to make the modal full width -

.modal-dialog {
    width: 100% }

3) Alternatively add in an extra class if you have other modals -

<div class="container">
    <div class="modal-dialog modal-responsive">
    </div>
</div>

.modal-responsive.modal-dialog {
    width: 100% }

4) Add in a row/columns if you want various sized modals -

<div class="container">
  <div class="row">
    <div class="col-md-4">
      <div class="modal-dialog modal-responsive">
       ...
      </div>
    </div>
  </div>
</div>