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Tailwind CSS flex Class

The flex utility class generates the following CSS when applied to an element.

CSS Output

CSS
.flex {
  display: flex;
}

Variants

Use these variant prefixes to apply flex conditionally:

responsive:flex

Use It

HTML
<div class="flex gap-4">
  <div class="p-4 bg-blue-500">1</div>
  <div class="p-4 bg-blue-500">2</div>
  <div class="p-4 bg-blue-500">3</div>
</div>

Understanding flex

The Tailwind CSS flex utility applies display: flex; to an element when added to its class attribute. It creates a block-level flex container, enabling the flexbox layout model for all direct children. Children become flex items that can be aligned, distributed, and sized along the main and cross axes.

This utility is part of Tailwind's Layout module, designed for controlling element display types, positioning methods, and document flow behavior. In Tailwind's utility-first workflow, you add flex directly to your HTML elements rather than writing custom CSS. This approach accelerates development and keeps styles co-located with your markup, making it easy to see exactly how each element is styled at a glance.

Common responsive variants include sm:flex, md:flex, lg:flex, and xl:flex, allowing different behavior at each breakpoint. State variants like hover:flex and focus:flex enable interactive styling without any JavaScript. You can also combine multiple variants for fine-grained control over when the utility applies.

This class works well alongside `inline-flex`, `grid`, `flex-row`, `flex-col` to build complete, production-ready interfaces. Tailwind's tree-shaking ensures only utilities you actually use appear in your final CSS bundle, keeping file sizes minimal. Browser support for the underlying CSS is excellent across Chrome, Firefox, Safari, and Edge.

Related Classes

inline-flex

display: inline-flex;

grid

display: grid;

flex-row

flex-direction: row;

flex-col

flex-direction: column;

items-center

align-items: center;

justify-center

justify-content: center;

Explore More Tailwind Classes

Browse our complete reference of 321 Tailwind CSS utility classes with CSS output, variants, and examples.

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