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Border Width

Utilities for controlling the width of an element's borders.

Default class reference

border-0border-width: 0px;
border-2border-width: 2px;
border-4border-width: 4px;
border-8border-width: 8px;
borderborder-width: 1px;
border-t-0border-top-width: 0px;
border-t-2border-top-width: 2px;
border-t-4border-top-width: 4px;
border-t-8border-top-width: 8px;
border-tborder-top-width: 1px;
border-r-0border-right-width: 0px;
border-r-2border-right-width: 2px;
border-r-4border-right-width: 4px;
border-r-8border-right-width: 8px;
border-rborder-right-width: 1px;
border-b-0border-bottom-width: 0px;
border-b-2border-bottom-width: 2px;
border-b-4border-bottom-width: 4px;
border-b-8border-bottom-width: 8px;
border-bborder-bottom-width: 1px;
border-l-0border-left-width: 0px;
border-l-2border-left-width: 2px;
border-l-4border-left-width: 4px;
border-l-8border-left-width: 8px;
border-lborder-left-width: 1px;

All sides

Use the border, .border-0, .border-2, .border-4, or .border-8 utilities to set the border width for all sides of an element.

<div class="border-0 border-indigo-600 ..."></div>
<div class="border border-indigo-600 ..."></div>
<div class="border-2 border-indigo-600 ..."></div>
<div class="border-4 border-indigo-600 ..."></div>
<div class="border-8 border-indigo-600 ..."></div>

Individual sides

Use the border-{side}, .border-{side}-0, .border-{side}-2, .border-{side}-4, or .border-{side}-8 utilities to set the border width for one side of an element.

<div class="border-t-2 border-fuchsia-600 ..."></div>
<div class="border-r-2 border-fuchsia-600 ..."></div>
<div class="border-b-2 border-fuchsia-600 ..."></div>
<div class="border-l-2 border-fuchsia-600 ..."></div>

Between elements

You can also add borders between child elements using the divide-{x/y}-{width} and divide-{color} utilities.

Learn more in the Divide Width and Divide Color documentation.

<div class="divide-y divide-light-blue-400 ...">


To control the border width of an element at a specific breakpoint, add a {screen}: prefix to any existing border width utility. For example, use md:border-t-4 to apply the border-t-4 utility at only medium screen sizes and above.

<div class="border-2 md:border-t-4 ..."></div>

For more information about Tailwind’s responsive design features, check out the Responsive Design documentation.


Border Widths

By default, Tailwind provides five border-width utilities, and the same number of utilities per side (top, right, bottom, and left). You change, add, or remove these by editing the theme.borderWidth section of your Tailwind config. The values in this section will also control which utilities will be generated side.

  // tailwind.config.js
  module.exports = {
    theme: {
      borderWidth: {
        DEFAULT: '1px',
        '0': '0',
        '2': '2px',
+       '3': '3px',
        '4': '4px',
+       '6': '6px',
-       '8': '8px',


By default, only responsive variants are generated for border width utilities.

You can control which variants are generated for the border width utilities by modifying the borderWidth property in the variants section of your tailwind.config.js file.

For example, this config will also generate hover and focus variants:

  // tailwind.config.js
  module.exports = {
    variants: {
      extend: {
        // ...
+       borderWidth: ['hover', 'focus'],


If you don't plan to use the border width utilities in your project, you can disable them entirely by setting the borderWidth property to false in the corePlugins section of your config file:

  // tailwind.config.js
  module.exports = {
    corePlugins: {
      // ...
+     borderWidth: false,