border-top-width#

#Introduction

The border-top-width CSS property sets the width of the left border of an element.

#Examples

css-apisrc/border-top-width/App.tsx

Code

Preview

#Syntax

/* Keyword values */
border-top-width: thin;
border-top-width: medium;
border-top-width: thick;

/* <length> values */
border-top-width: 10rem;
border-top-width: 6px;

#Values

<line-width>

Defines the width of the border, either as an explicit nonnegative <length> or a keyword. If it's a keyword, it must be one of the following values:

• thin
• medium
• thick

#Formal definition

#Formal syntax

border-top-width =
  <line-width>

<line-width> =
  <length [0,∞]>  |
  thin            |
  medium          |
  thick

#Difference from Web

• mdn:border-top-width

Global values are not supported (inherit, initial, revert, unset, etc).

Default value is 0, different to 'medium' in Web.

#Compatibility