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Summary

The float CSS property specifies that an element should be taken from the normal flow and placed along the left or right side of its container, where text and inline elements will wrap around it.

A floating element is one where the computed value of float is not none.

Initial valuenone
Applies toall elements, but has no effect if the value of display is none.
Inheritedno
Mediavisual
Computed valueas specified
Animation typediscrete
Canonical orderthe unique non-ambiguous order defined by the formal grammar

As float implies the use of the block layout, it modifies the computed value of the display values in some cases:

Specified value Computed value
inline block
inline-block block
inline-table table
table-row block
table-row-group block
table-column block
table-column-group block
table-cell block
table-caption block
table-header-group block
table-footer-group block
flex flex, but float has no effect on such elements
inline-flex inline-flex, but float has no effect on such elements
other unchanged
Note: If you're referring to this property from JavaScript as a member of the element.style object, you must spell it as cssFloat. Also note that Internet Explorer versions 8 and older spelled this styleFloat. This is an exception to the rule that the name of the DOM member is the camel-case name of the dash-separated CSS name (and is due to the fact that "float" is a reserved word in JavaScript, as with the need to escape "class" as "className" and escape <label>'s "for" as "htmlFor").

Syntax

float: left;
float: right;
float: none;
float: inline-start;
float: inline-end;

/* Global values */
float: inherit;
float: initial;
float: unset;

Values

left
Is a keyword indicating that the element must float on the left side of its containing block.
right
Is a keyword indicating that the element must float on the right side of its containing block.
none
Is a keyword indicating that the element must not float.
inline-start
Is a keyword indicating that the element must float on the start side of its containing block, that is the left side on ltr scripts and the right side on rtl scripts.
inline-end
Is a keyword indicating that the element must float on the end side of its containing block, that is the right side on ltr scripts and the left side on rtl scripts.

Formal syntax

left | right | none | inline-start | inline-end

Examples

HTML

<style type="text/css">
  div { border: solid red;  max-width: 70ex; }
  h4  { float: left;  margin: 0; }
</style>

<div>
  <h4>HELLO!</h4>
  This is some text. This is some text. This is some text.
  This is some text. This is some text. This is some text.
  This is some text. This is some text. This is some text.
  This is some text. This is some text. This is some text.
</div>

HELLO!

This is some text. This is some text. This is some text. This is some text. This is some text. This is some text. This is some text. This is some text. This is some text. This is some text. This is some text. This is some text.

 

How floats are positioned

As mentioned above, when an element is floated it is taken out of the normal flow of the document. It is shifted to the left or right until it touches the edge of its containing box or another floated element.

In the image below, there are three red squares. Two are floated left and one is floated right. Note that the second "left" red square is placed to the right of the first. Additional squares would continue to stack to the right until they filled the containing box, after which they would wrap to the next line.

Clearing floats

In the example above, the floated elements are shorter vertically than the block of text they're floated within. However, if the text was not long enough to wrap below the bottom of all the floats, we might see unanticipated effects. If the paragraph above, for instance, only read "Lorem ipsum dolor sit amet," and was followed by another heading of the same style as the "Floats Example" heading, the second heading would appear between the red boxes. Most likely, we want the next heading to be aligned all the way to the left. To accomplish that, we'd need to clear the floats.

The simplest way to clear the floats in this example is to add the clear property to the new heading we want to be sure is aligned left:

h2.secondHeading { clear: both; }

However, this method only works if there are no other elements within the same block formatting context that we do want the heading to continue to appear next to horizontally. If our H2 has siblings which are a sidebars floated to the left and right, using clear will force it to appear below both sidebars, which is probably not what we want.

If clearing floats on an element below them is not an option, another approach is to limit the block formatting context of the floats' container. Referring to the example above again, it appears that all three red boxes are within a P element. We can set the overflow property on that P to hidden or auto to cause it to expand to contain them, but not allow them to drop out the bottom of it:

p.withRedBoxes { overflow: hidden; height: auto; }
Note: Setting overflow to scroll will also contain any floated child elements, but will show scrollbars no matter the height of the content. Here we're setting height to auto even though that's the default to indicate that the container should grow to accommodate its content.

Specifications

Specification Status Comment
CSS Logical Properties Level 1
The definition of 'float and clear' in that specification.
Editor's Draft Adds the values inline-start and inline-end.
CSS Basic Box Model
The definition of 'float' in that specification.
Working Draft Lots of new values, not all clearly defined yet. Any differences in behavior unrelated to new features are expected to be unintentional; please report.
CSS Level 2 (Revision 1)
The definition of 'float' in that specification.
Recommendation No change
CSS Level 1
The definition of 'float' in that specification.
Recommendation Initial definition

Browser compatibility

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari
Basic support 1.0 (Yes) 1.0 (1.7 or earlier) 4.0 7.0 1.0
inline-start, inline-end No support ? 45 (45) [1] No support No support No support
Feature Android Edge Firefox Mobile (Gecko) Firefox OS IE Mobile Opera Mobile Safari Mobile
Basic support 1.0 (Yes) 1.0 (1) 1.0 6.0 6.0 1.0
inline-start, inline-end No support ? 45.0 (45) [1] 2.5 No support No support No support

[1] Enabled by default on Nightly and Aurora (Dev edition); to activate it on a release or beta version, you need to flip the layout.css.float-logical-values.enabled to true.

See also