MDN’s new design is in Beta! A sneak peek: https://blog.mozilla.org/opendesign/mdns-new-design-beta/

Summary

The CSS place-items shorthand property sets both the align-items and justify-items properties. The first value is the align-items property value, the second the justify-items one. If the second value is not present, the first value is also used for it.

Syntax

/* Keyword values */ 
place-items: auto center; 
place-items: normal start; 

/* Positional alignment */ 
place-items: center normal; 
place-items: start auto; 
place-items: end normal; 
place-items: self-start auto; 
place-items: self-end normal; 
place-items: flex-start auto; 
place-items: flex-end normal; 
place-items: left auto; 
place-items: right normal; 

/* Baseline alignment */ 
place-items: baseline normal; 
place-items: first baseline auto; 
place-items: last baseline normal; 
place-items: stretch auto; 

/* Global values */ 
place-items: inherit; 
place-items: initial; 
place-items: unset;

Values

auto
The value used is the value of the justiy-items property of the parents box, unless the box has no parent, or is absolutely positioned, in these cases, auto represents normal.
normal
The effect of this keyword is dependent of the layout mode we are in:
  • In block-level layouts, the keyword is a synonym of start.
  • In absolutely-positioned layouts, the keyword behaved like start on replaced absolutely-positioned boxes, and as stretch on all other absolutely-positioned boxes.  
  • In table cell layouts, this keyword has no meaning as this property is ignored.
  • In flexbox layouts, this keyword has no meaning as this property is ignored.
  • In grid layouts, this keyword leads to a behavior similar to the one of stretch, except for boxes with an aspect ratio or an intrinsic sizes where it behaves like start.
start
The item is packed flush to each other toward the start edge of the alignment container in the appropriate axis.
end
The item is packed flush to each other toward the end edge of the alignment container in the appropriate axis.
flex-start
The item ispacked flush to each other toward the edge of the alignment container depending on the flex container's main-start or cross-start side.
This only applies to flex layout items. For items that are not children of a flex container, this value is treated like start.
flex-end
The item is packed flush to each other toward the edge of the alignment container depending on the flex container's main-end or cross-end side.
This only applies to flex layout items. For items that are not children of a flex container, this value is treated like end.
self-start
The item is packed flush to the edge of the alignment container of the start side of the item, in the appropriate axis.
self-end
The item is packed flush to the edge of the alignment container of the end side of the item, in the appropriate axis.
center
The items are packed flush to each other toward the center of the of the alignment container.
left
The items are packed flush to each other toward the left edge of the alignment container. If the property’s axis is not parallel with the inline axis, this value behaves like start.
right
The items are packed flush to each other toward the right edge of the alignment container in the appropriate axis. If the property’s axis is not parallel with the inline axis, this value behaves like start.
baseline
first baseline

last baseline
Specifies participation in first- or last-baseline alignment: aligns the alignment baseline of the box’s first or last baseline set with the corresponding baseline in the shared first or last baseline set of all the boxes in its baseline-sharing group.
The fallback alignment for first baseline is start, the one for last baseline is end.
stretch
If the combined size of the items is less than the size of the alignment container, any auto-sized items have their size increased equally (not proportionally), while still respecting the constraints imposed by max-height/max-width (or equivalent functionality), so that the combined size exactly fills the alignment container.

Examples

CSS

#container {
  height:200px;
  width: 240px;
  place-items: center; /* You can change this value by selecting another option in the list */
  background-color: #8c8c8c;
}

.flex {
  display: flex;
  flex-wrap: wrap;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, 50px);
}

Result

Specifications

Specification Status Comment
CSS Box Alignment Module
The definition of 'place-items' in that specification.
Working Draft Initial definition

Browser compatibility

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari
Basic support 59 ? 45.0 (45.0) ? ? ?
Feature Android Webview Chrome for Android Edge Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support 59 59 ? 45.0 (45.0) ? ? ?

Document Tags and Contributors

 Contributors to this page: jpmedley, SphinxKnight, teoli
 Last updated by: jpmedley,