CSS margin-block Property Reference

The CSS margin-block property is a standard property in CSS Logical Properties and Values. Review its formal syntax, computed behavior, and practical declarations.

Updated 2026-08-12

margin-block overview

The CSS margin-block property is a standard property in CSS Logical Properties and Values. Review its formal syntax, computed behavior, and practical declarations.

The property is not inherited by default. Use an explicit global keyword when inheritance is intended.

Syntax and formal definition

margin-block formal syntax

Field	Value
Formal syntax	<'margin-top'>{1,2}
Initial value	margin-block-start, margin-block-end
Applies to	sameAsMargin
Inherited	No
Percentages	dependsOnLayoutModel
Computed value	margin-block-start, margin-block-end
Animation type	length
Media	visual
Specification group	CSS Logical Properties and Values
Status	Standard

Practical examples

These declarations demonstrate valid ways to set margin-block. The initial and inherit global keywords remain available even when a property-specific value is preferable.

margin-block live example

CSS

.reset-example {
  margin-block: initial;
}

.inherit-example {
  margin-block: inherit;
}

@supports (margin-block: initial) {
  .supported {
    margin-block: initial;
  }
}