How to vertically center a div on page? [duplicate]

Answer 1

You can do that with flexboxes:

html,body {
  height: 100%;
  min-height: 100%;
}
.Aligner {
  display: flex;
  align-items: center;
  justify-content: center;
  height: 100%;
  min-height: 100%;
}

.Aligner-item {
  max-width: 50%;
  background-color: red;
}

<div class="Aligner">
  <div class="Aligner-item">…</div>
</div>

Answer 2

The three lines below should suffice:

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

Answer 3

.parent {
  text-align: center;
  white-space: nowrap;
}     
.parent:before {
  content: '';
  display: inline-block;
  height: 100%;
  vertical-align: middle;
  margin-right: -0.25em;
}
.child {
  display: inline-block;
  vertical-align: middle;
  width: 300px;
}

Answer 4

HTML

<div class="container"><div class="your-div"></div></div>

CSS

body, html{
    display:table;
    height:100%;
    width:100%;
}
.container{
    display:table-cell;
    vertical-align:middle;
}
.container .your-div{
    width:150px;
    height:150px;
    background:green;
    margin:0 auto;   
}

Answer 5

add a wrapper div; box-wrapper

#box-wrapper {
    position: relative;
}
#box {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}

by the way much detailed explanation can be found on css-tricks.com/centering-css-complete-guide

Answer 6

Method 1 (position, transform-translate):

* {
  padding: 0;
  margin: 0;
}
.parent {
  position: relative;
  left: 0;
  top: 0;
  width: 100vw;
  height: 100vh;
  background-color: gray;
}
.child {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  width: 10em;
  height: 5em;
  background-color: white;
  box-shadow: 1px 1px 10px rgba(0,0,0,.4);
}

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

Method 2 (Flexbox):

* {
  padding: 0;
  margin: 0;
}

.parent {
  position: fixed;
  left: 0;
  top: 0;
  width: 100vw;
  height: 100vh;
  background-color: gray;
  display: flex;
}

.child {
  margin: auto;
  width: 10em;
  height: 5em;
  background-color: white;
  box-shadow: 1px 1px 10px rgba(0, 0, 0, .4);
}

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