border-block-width
Sets the thickness of the borders in the block dimension (usually top and bottom). It's a convenient way to adjust the vertical thickness of a box's borders simultaneously.
Quick example
.divider {
border-block-style: solid;
/* sets 2px thickness for both top and bottom edges */
border-block-width: 2px;
border-block-color: #333;
}Quick facts
Initial value
mediumInherited
No
Applies to
all elements
Animation type
byComputedValueType
Values
border-top-width border-block-width Browser Support
Widely available Since 2021 95% global usage
This feature is well established and works across many devices and browser versions. It has been available across browsers since 2021.
Safe to use without fallbacks.
87+
66+
14.1+
87+