CSS overflow

The CSS overflow property is used for setting the clipping behavior on an element. It determines what to do when a box's contents are too large to fit inside. For example, you could specify that a box grows scroll bars whenever its contents get too large to fit inside. Alternatively, you could specify that the contents are simply hidden from view.

As of CSS3, the overflow property is a shorthand property for the overflow-x and overflow-y properties (this is because those properties were only introduced in CSS3). The overflow property allows you to set both of those properties at once. Therefore, the overflow property is a time-efficient and code-efficient way of setting your "overflow-related" properties.

Syntax

Possible Values

The overflow property is shorthand, and accepts one or two keywords (below). If it has one keyword, that keyword sets both overflow-x and overflow-y; if it has two keywords, it sets overflow-x to the first and overflow-y to the second

visible

Specifies that the content should not be clipped. In other words, it should be displayed outside the content box.

hidden

Specifies that the content is clipped (i.e. the parts that extend beyond the content box are hidden), and no scroll bars (or other scrolling mechanism) are supplied.

clip

Like hidden, this value indicates that the box's content is clipped to its padding box and that no scrolling user interface should be provided. In addition, unlike overflow: hidden which still allows programmatic scrolling, overflow: clip forbids scrolling entirely, through any mechanism, and therefore the box is not a scroll container.

scroll

Specifies that the content box should provide scroll bars (or other scrolling mechanism) regardless of whether the content is clipped or not.

auto

Specifies that the content box should provide scroll bars (or other scrolling mechanism) only when the content overflows (i.e. is too big to fit within the content box).

In addition, all CSS properties also accept the following CSS-wide keyword values as the sole component of their property value:

initial

Represents the value specified as the property's initial value.

inherit

Represents the computed value of the property on the element's parent.

unset

This value acts as either inherit or initial, depending on whether the property is inherited or not. In other words, it sets all properties to their parent value if they are inheritable or to their initial value if not inheritable.

Basic Property Information

Example Code

Basic CSS

Working Example within an HTML Document

CSS Specifications

• CSS Overflow Module Level 3
• CSS Level 2.1

Browser Support

Browser support for CSS properties can vary, particularly for newer or experimental features. Check current browser compatibility before using a property in production, especially when supporting older browsers.

The following table provided by Caniuse.com shows the level of browser support for this feature.

Initial Value

CSS properties have an initial value that applies when the property has not been explicitly set. The initial value is different from the value inherited from a parent element and may vary between properties.

Inheritance

Some CSS properties inherit their computed value from their parent element by default, while others do not. The inherit, initial, unset, and revert keywords can also be used to control how a property gets its value.

Vendor Prefixes

Most modern CSS properties use the standard, unprefixed syntax. Vendor-prefixed properties such as -webkit- are mainly relevant to older browser versions or specific features and should only be used when required by your browser support targets.