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Free CSS Flexbox Generator

Generate a complete CSS flexbox container declaration from direction, justify-content, align-items, wrap, and gap.

100% Free No Signup Works on all devices

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Key Features

Instant Calculation

Get accurate results in real time with our optimized algorithm.

Mobile Friendly

Fully responsive design. Works on all devices & screen sizes.

Privacy Focused

Your data stays on your device. We don't store any inputs.

100% Free

No hidden costs. This tool is completely free forever.

Flexbox layout depends on five properties working together — direction, justify-content, align-items, wrap, and gap — and remembering exactly which property controls which axis is one of the most common points of confusion when writing flexbox CSS from memory.

This generator builds a complete flex container declaration from your chosen layout options.

How it works

Choose the flex direction, justify-content (main-axis alignment), align-items (cross-axis alignment), flex-wrap behavior, and an optional gap. The generator assembles all five properties (plus <code>display: flex;</code>) into a single ready-to-use CSS block.

  1. Enter flex direction.
  2. Enter justify content.
  3. Enter align items.
  4. Enter flex wrap.
  5. Enter gap (px, optional).
  6. Click Calculate to see your results.

Examples

Centered row layout

A row direction with center justify-content and center align-items centers flex items both horizontally and vertically within the container.

Who should use it

  • Quickly scaffolding a flexbox layout without looking up property names and values from memory.
  • Learning how flexbox's core properties combine to produce a given layout.

Industry applications

  • Web design and front-end development
  • Responsive web design

Advantages

  • Generates all five key flexbox container properties together in one block.
  • Covers the full range of justify-content and align-items options.

Limitations

  • Only generates container-level properties — doesn't cover individual flex item properties like flex-grow or order.

Common mistakes to avoid

  • Confusing which axis justify-content versus align-items controls — this flips depending on whether flex-direction is row or column.
  • Forgetting flex-wrap: wrap when a row of items needs to wrap onto multiple lines on smaller screens.

Best practices

  • Remember that switching flex-direction to column swaps which axis justify-content and align-items each control — re-check your alignment choices whenever you change direction.

Tips

  • For a responsive layout where items should wrap onto new rows on narrow screens, combine flex-wrap: wrap with a gap value instead of individual item margins — it handles spacing consistently even as items wrap.

Frequently asked questions

Yes, with no signup and no limit on how many declarations you generate.
justify-content aligns items along the main axis (the direction flex-direction points), while align-items aligns items along the cross axis (perpendicular to the main axis) — for a row direction, that's horizontal versus vertical alignment respectively.
It controls whether flex items are forced onto a single line (nowrap, the default) or allowed to wrap onto multiple lines (wrap) when they don't all fit — essential for responsive layouts with many items.
It adds consistent spacing between flex items without needing individual margins on each one — a modern, simpler alternative to margin-based spacing hacks.

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