Non-standard: This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.

Deprecated: This feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.

The non-standard -moz-float-edge CSS property specifies whether the height and width properties of the element include the margin, border, or padding thickness.

/* Keyword values */
-moz-float-edge: border-box;
-moz-float-edge: content-box;
-moz-float-edge: margin-box;
-moz-float-edge: padding-box;

/* Global values */
-moz-float-edge: inherit;
-moz-float-edge: initial;
-moz-float-edge: unset;




The height and width properties include the content, padding and border but not the margin.


The height and width properties include the content, but not the padding, border or margin.


The height and width properties include the content, padding, border and margin.


The height and width properties include the content and padding but not the border or margin.

Formal definition

Initial valuecontent-box
Applies toall elements
Computed valueas specified
Animation typediscrete

Formal syntax

-moz-float-edge =
  border-box | content-box | margin-box | padding-box



<div class="box">
  <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit.</p>


.box {
  display: block;
  height: 5px;
  margin: 0.5em auto 0.5em auto;
  color: gray;
  -moz-float-edge: margin-box;
  box-sizing: border-box;



Not part of any standard.

Browser compatibility

BCD tables only load in the browser

See also