Using jQuery to center a DIV on the screen

Using jQuery to center a DIV on the screen

How do I go about setting a

in the center of the screen using jQuery?

Solutions/Answers:

Solution 1:

I like adding functions to jQuery so this function would help:

jQuery.fn.center = function () {
    this.css("position","absolute");
    this.css("top", Math.max(0, (($(window).height() - $(this).outerHeight()) / 2) + 
                                                $(window).scrollTop()) + "px");
    this.css("left", Math.max(0, (($(window).width() - $(this).outerWidth()) / 2) + 
                                                $(window).scrollLeft()) + "px");
    return this;
}

Now we can just write:

$(element).center();

Demo: Fiddle (with added parameter)

Solution 2:

I put a jquery plugin here

VERY SHORT VERSION

$('#myDiv').css({top:'50%',left:'50%',margin:'-'+($('#myDiv').height() / 2)+'px 0 0 -'+($('#myDiv').width() / 2)+'px'});

SHORT VERSION

(function($){
    $.fn.extend({
        center: function () {
            return this.each(function() {
                var top = ($(window).height() - $(this).outerHeight()) / 2;
                var left = ($(window).width() - $(this).outerWidth()) / 2;
                $(this).css({position:'absolute', margin:0, top: (top > 0 ? top : 0)+'px', left: (left > 0 ? left : 0)+'px'});
            });
        }
    }); 
})(jQuery);

Activated by this code :

$('#mainDiv').center();

PLUGIN VERSION

(function($){
     $.fn.extend({
          center: function (options) {
               var options =  $.extend({ // Default values
                    inside:window, // element, center into window
                    transition: 0, // millisecond, transition time
                    minX:0, // pixel, minimum left element value
                    minY:0, // pixel, minimum top element value
                    withScrolling:true, // booleen, take care of the scrollbar (scrollTop)
                    vertical:true, // booleen, center vertical
                    horizontal:true // booleen, center horizontal
               }, options);
               return this.each(function() {
                    var props = {position:'absolute'};
                    if (options.vertical) {
                         var top = ($(options.inside).height() - $(this).outerHeight()) / 2;
                         if (options.withScrolling) top += $(options.inside).scrollTop() || 0;
                         top = (top > options.minY ? top : options.minY);
                         $.extend(props, {top: top+'px'});
                    }
                    if (options.horizontal) {
                          var left = ($(options.inside).width() - $(this).outerWidth()) / 2;
                          if (options.withScrolling) left += $(options.inside).scrollLeft() || 0;
                          left = (left > options.minX ? left : options.minX);
                          $.extend(props, {left: left+'px'});
                    }
                    if (options.transition > 0) $(this).animate(props, options.transition);
                    else $(this).css(props);
                    return $(this);
               });
          }
     });
})(jQuery);

Activated by this code :

$(document).ready(function(){
    $('#mainDiv').center();
    $(window).bind('resize', function() {
        $('#mainDiv').center({transition:300});
    });
);

is that right ?

UPDATE :

From CSS-Tricks

.center {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%); /* Yep! */
  width: 48%;
  height: 59%;
}

Solution 3:

I would recommend jQueryUI Position utility

$('your-selector').position({
    of: $(window)
});

which gives you much more possibilities than only centering …

Solution 4:

Here’s my go at it. I ended up using it for my Lightbox clone. The main advantage of this solution is that the element will stay centered automatically even if the window is resized making it ideal for this sort of usage.

$.fn.center = function() {
    this.css({
        'position': 'fixed',
        'left': '50%',
        'top': '50%'
    });
    this.css({
        'margin-left': -this.outerWidth() / 2 + 'px',
        'margin-top': -this.outerHeight() / 2 + 'px'
    });

    return this;
}

Solution 5:

You can use CSS alone to center like so:

Working Example

.center{
    position: absolute;
    height: 50px;
    width: 50px;
    background:red;
    top:calc(50% - 50px/2); /* height divided by 2*/
    left:calc(50% - 50px/2); /* width divided by 2*/
}
<div class="center"></div>

calc() allows you to do basic calculations in css.

MDN Documentation for calc()
Browser support table

Solution 6:

I’m expanding upon the great answer given by @TonyL. I’m adding Math.abs() to wrap the values, and also I take into account that jQuery might be in “no conflict” mode, like for instance in WordPress.

I recommend that you wrap the top and left values with Math.abs() as I have done below. If the window is too small, and your modal dialog has a close box at the top, this will prevent the problem of not seeing the close box. Tony’s function would have had potentially negative values. A good example on how you end up with negative values is if you have a large centered dialog but the end user has installed several toolbars and/or increased his default font — in such a case, the close box on a modal dialog (if at the top) might not be visible and clickable.

The other thing I do is speed this up a bit by caching the $(window) object so that I reduce extra DOM traversals, and I use a cluster CSS.

jQuery.fn.center = function ($) {
  var w = $(window);
  this.css({
    'position':'absolute',
    'top':Math.abs(((w.height() - this.outerHeight()) / 2) + w.scrollTop()),
    'left':Math.abs(((w.width() - this.outerWidth()) / 2) + w.scrollLeft())
  });
  return this;
}

To use, you would do something like:

jQuery(document).ready(function($){
  $('#myelem').center();
});