.container {
display: flex;
flex-direction: row;
justify-content: flex-start;
align-items: stretch;
flex-wrap: nowrap;
gap: 8px;
}Visual Flexbox generator with live preview. Adjust direction, alignment, distribution, and gap to create perfect layouts.
What is Flexbox Generator?
CSS Flexbox (Flexible Box Layout) is a one-dimensional layout system designed for distributing space along a single axis — either a row or a column. Items inside a flex container can grow to fill available space, shrink to prevent overflow, or remain at their natural size, depending on the properties you set. Flexbox solves layout problems that were notoriously difficult with older CSS techniques: vertically centering content, distributing equal-width columns, aligning items at the start or end of a container, and creating responsive navigation bars that adapt to varying content widths. The key concepts are the main axis (defined by flex-direction) and the cross axis (perpendicular to it). justify-content controls alignment along the main axis, align-items controls the cross axis, and the gap property provides consistent spacing between items without resorting to margins. This generator lets you configure all flex container properties visually and copy the resulting CSS.
How to Use
- Set flex-direction: row (horizontal) or column (vertical)
- Choose justify-content for main axis alignment
- Select align-items for cross axis alignment
- Enable flex-wrap for multi-line layouts
- Adjust gap for spacing between items
- Copy generated CSS to your stylesheet
Why Use This Tool?
Tips & Best Practices
- justify-content controls horizontal alignment in row, vertical in column
- align-items is the opposite axis from justify-content
- Use flex-wrap: wrap for responsive multi-line layouts
- gap replaces margin-based spacing
- center both axes: justify-content: center + align-items: center
- space-between distributes items with edges at start/end
Frequently Asked Questions
What is flex-direction?
flex-direction sets the main axis: row (horizontal, left-to-right), row-reverse (right-to-left), column (vertical, top-to-bottom), column-reverse (bottom-to-top). All other flex properties work relative to this main axis direction.
What's the difference between justify-content and align-items?
justify-content aligns items along the main axis (the direction set by flex-direction). align-items aligns along the cross axis (perpendicular to main axis). In row direction, justify is horizontal, align is vertical. In column, they swap.
When should I use flex-wrap?
Use flex-wrap: wrap when items might overflow the container width/height. Items wrap to multiple lines instead of shrinking. Essential for responsive layouts where content adapts to screen size.
What does gap property do?
gap sets spacing between flex items - both horizontal and vertical when wrap is enabled. Replaces margin-based spacing with simpler, more predictable behavior. Gap isn't added at edges (start/end of container).
How do I center content with flexbox?
Set justify-content: center (main axis) and align-items: center (cross axis). This centers items both horizontally and vertically regardless of flex-direction. The simplest way to center content in CSS.
Flexbox or Grid - which should I use?
Flexbox for one-dimensional layouts (single row/column): navigation, cards, centering. Grid for two-dimensional layouts (rows AND columns together): page structure, complex component layouts. Use Flexbox for component internals, Grid for page structure.
Is my layout data kept private?
Yes. All layout generation happens locally in your browser. No CSS values or layout configurations are ever sent to a server or stored anywhere.
When should I NOT use Flexbox?
Avoid Flexbox for two-dimensional layouts where you need to control both rows and columns simultaneously — use CSS Grid instead. Also skip it for strict typographic layouts with overlapping elements, or when you need items to align to a baseline grid across multiple unrelated containers. Flexbox is also not ideal for print layouts with precise page-break control.
Real-world Examples
Building a responsive navigation bar
A common navigation layout uses Flexbox to align the logo on the left and navigation links on the right, with even spacing between items.
Direction: row, Justify: space-between, Align: center, Gap: 16px
.nav {
display: flex;
flex-direction: row;
justify-content: space-between;
align-items: center;
gap: 16px;
}Centering a login form vertically and horizontally
The classic centering problem — placing content dead center in the viewport — is solved with just two Flexbox properties.
Direction: row, Justify: center, Align: center, Gap: 0px
.container {
display: flex;
flex-direction: row;
justify-content: center;
align-items: center;
gap: 0px;
}