CSS Flexbox Generator
Struggling with flexbox alignment? Our free CSS Flexbox Generator lets you visually design flex container layouts and export production-ready CSS code. Simply set the flex direction, justify-content, align-items, flex-wrap, gap, and other properties using intuitive controls — a live preview updates instantly so you can see exactly how your layout will look. Whether you're building a navbar, card grid, centering a div (finally!), or a complex dashboard layout, this tool makes flexbox predictable and readable. No more guessing values or fighting with margin hacks. Just drag, tweak, and copy the clean CSS output.
What Is
Flexbox (CSS Flexible Box Layout) is a one-dimensional layout method for arranging items in rows or columns. It solves many classic CSS problems: vertical centering, equal-height columns, reordering items without changing HTML, and distributing remaining space efficiently. Core concepts: • Flex container — the parent element with display: flex. All direct children become flex items. • Main axis — the primary direction items flow along, controlled by flex-direction (row | row-reverse | column | column-reverse). • Cross axis — the perpendicular direction. Alignment here is controlled by align-items (for single line) and align-content (for multi-line). • justify-content — aligns items along the main axis. Options include flex-start, flex-end, center, space-between, space-around, space-evenly. • align-items — aligns items along the cross axis. Options include stretch, flex-start, flex-end, center, baseline. • flex-wrap — controls whether items wrap to new lines (nowrap | wrap | wrap-reverse). • gap — spacing between items, replacing the need for margin hacks. Individual flex items can also be controlled with flex-grow, flex-shrink, flex-basis, align-self, and order. The shorthand flex: 1 is equivalent to flex: 1 1 0%. Browser support is universal — all modern browsers support flexbox with no prefixes. The spec has been stable since 2012, making it safe for production use.
How to Use
- Open the CSS Flexbox Generator. A sample container with several child items appears on the canvas.
- Set the container properties: choose flex-direction (row or column), select justify-content and align-items from dropdown menus, toggle flex-wrap if you want items to overflow onto new lines.
- Adjust spacing: use the gap slider to set uniform spacing between items, or set custom margin/padding values for individual items.
- Configure child items: for each flex item, set flex-grow, flex-shrink, flex-basis values, or use shorthand. Change order to rearrange visually without touching HTML.
- Experiment with alignment overrides: use align-self on individual items to override the container's align-items setting for that specific element.
- Copy the generated CSS output. The code includes display: flex, all configured properties, and optional vendor prefixes. Paste into your stylesheet and you're done.
Examples
Input: Direction: row, Justify: space-between, Align: center, Gap: 16px
Process: Set main axis horizontal → Distribute items with equal spacing → Vertically center
Result: display:flex; flex-direction:row; justify-content:space-between; align-items:center; gap:16px
Input: Direction: column, Wrap: wrap, Align-items: stretch
Process: Vertical stacking → Allow wrapping → Stretch items to full width
Result: display:flex; flex-direction:column; flex-wrap:wrap; align-items:stretch
Input: 3 items with flex-grow: 1, 2, 1
Process: Total grow ratio = 1+2+1=4 → Item1=25%, Item2=50%, Item3=25%
Result: Item widths: 25% | 50% | 25%
Related Searches
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Frequently Asked Questions
What is the difference between flex and grid?
Flexbox is one-dimensional — it layouts items along a single axis (row OR column). CSS Grid is two-dimensional — it handles rows AND columns simultaneously. Use flexbox for linear layouts like navbars, button groups, or centering content. Use grid for full-page layouts, complex card grids, or any design requiring precise control over both rows and columns. Many real-world layouts combine both: grid for the overall page structure, flexbox for component-level alignment.
How do I center a div with flexbox?
Apply display: flex to the parent container, then set justify-content: center for horizontal centering and align-items: center for vertical centering. That's it — no absolute positioning, no negative margins, no JavaScript. This is THE canonical use case for flexbox and it works reliably across all browsers. If you're centering a single child, this approach is simpler and more robust than any other method.
What does flex: 1 mean exactly?
flex: 1 is a shorthand for flex: 1 1 0% — meaning flex-grow: 1, flex-shrink: 1, flex-basis: 0%. This tells the item to grow and shrink as needed, starting from zero width. When multiple siblings have flex: 1, they each get an equal share of the remaining space. If one item has flex: 2 and others have flex: 1, the first item gets twice the proportion of free space compared to its siblings.
When should I use gap instead of margin?
Use gap (row-gap and column-gap) when you want spacing between flex items. Gap only applies between siblings — it doesn't create extra space at the edges of the container. This is a key advantage over margin, which adds space everywhere including the first and last items. With gap, you don't need :last-child or :not(:last-child) selectors to remove trailing margins anymore. Gap works in all modern browsers since 2021.
Can I change the visual order of items without changing HTML?
Yes! Use the order property on flex items. The default order value is 0. Items with lower order values appear first, regardless of their position in the HTML source. For example, setting order: -1 moves an item to the beginning. This is useful for responsive design — you might want a sidebar to appear below content on mobile but beside it on desktop. Note that order changes visual rendering only; it does not change DOM order or tab order for keyboard navigation.