CSS gap

The CSS gap property is shorthand for the column-gap and row-gap properties.

It specifies spacing between columns and rows in flexbox containers and grid containers, and columns in multi-column containers.

You can specify the gap to be either normal or to be a specific size (for example, a value of 30px would create a gap of 30 pixels).

Multi-Column Layout

Here's an example of gap being used on a multi-column container.

Flexbox Layout

Here's an example of gap being used on a flex container.

Grid Layout

Here's an example of gap being used on a grid container (this is the same example that's displayed at the top of this article).

Syntax

This means that the first value provides the row-gap, and the second provides the column-gap.

If 'row-gap' is omitted, it's set to the same value as 'column-gap'.

Possible Values

Here are the values that are accepted for each argument.

<length-percentage>

Specifies the width of the gap. For example, 40px would create a column gap of 40 pixels. Cannot be a negative value.

Note that <length-percentage> is equivalent to [ <length> | <percentage> ]. In other words, you can provide a <length> or <percentage> value.

normal

Represents a used value of 1em on multi-column containers, and a used value of 0px in all other contexts.

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

History of gap & grid-gap

The CSS Grid Layout module was originally written with its own set of gutter properties (grid-gap, grid-column-gap, and grid-row-gap). Those properties were later unified into the gap/row-gap/column-gap naming, which also expanded the scope to include flexbox containers, grid containers and multi-column containers.

For compatibility purposes, those grid-* property names are now aliases for the properties with the new names.

Specifically:

• grid-column-gap is an alias for column-gap
• grid-row-gap is an alias for row-gap
• grid-gap is an alias for gap

CSS Specifications

The gap property is defined in CSS Box Alignment Module Level 3.

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.