How to vertically center <div> inside the parent element with CSS? [duplicate]

Question

The best approach in modern browsers is to use flexbox:

#Login {
    display: flex;
    align-items: center;
}

Some browsers will need vendor prefixes. For older browsers without flexbox support (e.g. IE 9 and lower), you'll need to implement a fallback solution using one of the older methods.

Recommended Reading

• Browser support
• A Guide to Flexbox
• Using CSS Flexible Boxes

This can be done with 3 lines of CSS and is compatible back to (and including) IE9:

.element {
  position: relative;
  top: 50%;
  transform: translateY(-50%);
}

Example: http://jsfiddle.net/cas07zq8/

credit

You can vertically align a div in another div. See this example on JSFiddle or consider the example below.

HTML

<div class="outerDiv">
    <div class="innerDiv"> My Vertical Div </div>
</div>

CSS

.outerDiv {
    display: inline-flex;  // <-- This is responsible for vertical alignment
    height: 400px;
    background-color: red;
    color: white;
}

.innerDiv {
    margin: auto 5px;   // <-- This is responsible for vertical alignment
    background-color: green;   
}

The .innerDiv's margin must be in this format: margin: auto *px;

[Where, * is your desired value.]

display: inline-flex is supported in the latest (updated/current version) browsers with HTML5 support.

It may not work in Internet Explorer :P :)

Always try to define a height for any vertically aligned div (i.e. innerDiv) to counter compatibility issues.

I'm pretty late to the party, but I came up with this myself and it's one of my favorite quick hacks for vertical alignment. It's crazy simple, and easy to understand what's going on.

You use the :before css attribute to insert a div into the beginning of the parent div, give it display:inline-block and vertical-align:middle and then give those same properties to the child div. Since vertical-align is for alignment along a line, those inline divs will be considered a line.

Make the :before div height:100%, and the child div will automatically follow and align in the middle of a very tall "line."

.parent:before, .child {
    display:inline-block;
    vertical-align:middle;
}
.parent:before {
    content:""; // so that it shows up
    height:100%; // so it takes up the full height
}

Here's a fiddle to demonstrate what I'm talking about. The child div can be any height, and you never have to modify its margins/paddings.
And here's a more explanatory fiddle.

If you're not fond of :before, you can always manually put in a div.

<div class="parent">
    <div class="before"></div>
    <div class="child">
        content
    </div>
</div>

And then just reassign .parent:before to .parent .before

If you know the height, you can use absolute positioning with a negative margin-top like so:

#Login {
    width:400px;
    height:400px;
    position:absolute;
    top:50%;
    left:50%;
    margin-left:-200px; /* width / -2 */
    margin-top:-200px; /* height / -2 */
}

Otherwise, there's no real way to vertically center a div with just CSS

In my firefox and chrome work this:

CSS:

display: flex;
justify-content: center;     // vertical align
align-items: center;         // horizontal align