CSS

Flexbox Generator

Adjust the controls to configure your flex container. Copy the CSS when it looks right.

CSS 
.flex-container {
  display: flex;
  flex-direction: row;
  justify-content: flex-start;
  align-items: center;
  align-content: flex-start;
  flex-wrap: nowrap;
  gap: 8px;
}

Related Tools

What is the CSS Flexbox Generator?

CSS Flexbox is a one-dimensional layout model — it distributes space along a single row or column and handles alignment, ordering, and wrapping. This free online tool lets you configure every flex container property and see how items respond before writing a line of code.

How to use it

Select values for flex-direction, justify-content, align-items, and flex-wrap. Drag the gap slider to set spacing. The five colored boxes in the preview shift in real time. When the layout matches what you need, click Copy CSS and paste the .flex-container rule into your stylesheet.

Example

.nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
}

This is the most common flexbox pattern — a horizontal bar with the logo pushed to the left and links aligned to the right.

Tips and best practices

  • Use space-between for nav bars, center for hero sections, and flex-start for stacked form rows.
  • Prefer gap over margins — it doesn't add space before the first item or after the last, so no negative-margin hacks are needed.
  • Add flex-wrap: wrap with a fixed width on each child for a simple responsive card grid without any media queries.

Common mistakes

  • Using Flexbox for a two-dimensional layout (rows and columns at the same time) — that's what CSS Grid is for.
  • Forgetting min-width: 0 on a flex item — without it, a long word or wide image can push the item past the container edge.
  • Setting align-content on a single-line container — it has no effect unless flex-wrap: wrap is also set.

Frequently asked questions

When should I use Flexbox instead of CSS Grid?
Use Flexbox for one-dimensional flows — a single row or column. Use Grid when you need to control both rows and columns simultaneously.

Why is my flex item overflowing the container?
Items won't shrink below their content size by default. Add min-width: 0 or overflow: hidden to the overflowing item.

Does gap work in older browsers?
Flexbox gap is supported in Chrome 84+, Firefox 63+, and Safari 14.1+. For older support, use margins as a fallback.

The Button Generator and Box Shadow Generator are useful companions when polishing the components inside your flex layouts.

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