🗀 CSS Layout Generator
Visual Flexbox and Grid layout builder with live preview. Configure properties, add items, and copy production-ready CSS and HTML. Runs in your browser.
Last updated: May 18, 2026 · By Λ
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CSS Layout Generator - Build Flexbox and Grid Layouts Visually
CSS layout is the backbone of modern web design. The two most powerful layout systems available today are Flexbox and CSS Grid, each with their own strengths and ideal use cases. However, getting all the property values right by hand can be tedious and error-prone, especially when you need to account for item alignment, spacing, wrapping, and responsive behavior. This tool gives you a visual interface to experiment with both systems, see the results in real time, and copy production-ready code when you are done.
What Is This Tool?
This CSS Layout Generator lets you build Flexbox and Grid layouts using a point-and-click interface instead of writing code from scratch. You start by choosing a layout mode, either Flexbox or Grid. Then you configure container-level properties like direction, alignment, gap, and wrapping. You can add up to twelve child items and fine-tune per-item properties such as flex-grow, flex-shrink, order, grid-column, and grid-row. The preview area updates instantly as you make changes, so you always know exactly what your layout will look like. When you are satisfied, copy the CSS and HTML output and paste it into your project. The whole builder is self-contained on this page, so the layouts you experiment with never leave your machine.
How to Use This Tool
Start by selecting either the Flexbox or Grid tab. In Flexbox mode, configure the container using dropdowns for flex-direction, flex-wrap, justify-content, align-items, and align-content. Set the gap between items using the gap input. Click "Add Item" to create child boxes, each shown as a numbered pastel-colored block in the preview. Expand any item to adjust its flex-grow, flex-shrink, flex-basis, align-self, or order. In Grid mode, define your rows and columns using standard CSS track syntax like "1fr 1fr 1fr" or "repeat(3, 1fr)" or "200px auto 1fr". Set row-gap and column-gap, and configure justify-items, align-items, justify-content, and align-content. Per-item controls let you set grid-column and grid-row for spanning. Toggle grid lines on to visualize the grid tracks. Use the built-in presets to quickly load common layouts like Holy Grail, Sidebar, Card Grid, Centered Content, Navigation Bar, or Footer Columns.
Key Features
The live preview updates instantly as you change any property, giving you immediate visual feedback. Both Flexbox and Grid are supported in a single tool, so you can compare the two systems side by side. Container-level controls cover every major property for each layout mode. Per-item controls let you customize individual children with flex-grow, flex-shrink, flex-basis, align-self, order, grid-column, and grid-row. Six built-in presets provide quick starting points for the most common layout patterns. The CSS output shows clean, formatted code that you can paste directly into a stylesheet. The HTML output provides the corresponding markup. A grid lines overlay helps you visualize track boundaries. The tool is fully responsive and works on any screen size. No sign-up, no tracking, no external dependencies.
Frequently Asked Questions
When should I use Flexbox vs Grid? Flexbox is best for one-dimensional layouts where items flow in a single direction, either in a row or a column. It is ideal for navigation bars, card rows, centering content, and distributing space along one axis. Grid is best for two-dimensional layouts where you need control over both rows and columns simultaneously, such as full page layouts, dashboards, and complex card grids.
What does flex-grow do? flex-grow determines how much of the available free space an item should take relative to other items. If one item has flex-grow: 2 and another has flex-grow: 1, the first item will receive twice as much of the remaining space.
How do I make a grid item span multiple columns or rows? Use the grid-column and grid-row properties. For example, setting grid-column to "1 / 3" makes the item span from column line 1 to column line 3, covering two columns. You can also use "span 2" as shorthand.
Can I use both Flexbox and Grid in the same project? Absolutely. Most modern layouts use a combination of both. A common pattern is to use Grid for the overall page structure and Flexbox for the internal alignment of components within each grid area.
Are the generated layouts responsive? The CSS output uses flexible units like fr and auto where appropriate, which naturally adapts to different screen sizes. For production use, you may want to add media queries for specific breakpoint behavior.
Does this tool send my data anywhere? No. Every property change is computed by the page's own script and rendered straight into the preview, with no request carrying your configuration anywhere.
Why does the same preset look different in Flexbox and Grid mode? Each preset name exists twice, with a separate definition per mode. The Grid version of Holy Grail, for instance, uses a "200px 1fr 200px" column template and spans the header and footer with grid-column "1 / -1", while the Flexbox version approximates the shape by stacking five boxes in a column. Comparing the two definitions of one preset is a quick way to learn how the systems differ.
Why does clicking a preset wipe the items I added? Presets are full snapshots, not patches. Loading one resets the container properties and rebuilds the item list from scratch (Card Grid creates six items, Nav Bar five, Centered just one), so apply the preset first and customize afterward.
Do I lose my Flexbox setup when I switch to the Grid tab? No. The two modes keep separate item lists and container settings, so you can flip between tabs and each layout stays exactly as you left it.
Why does the Add Item button stop at twelve? The preview assigns each block one of twelve pastel colors, and twelve children are plenty for testing alignment and spanning behavior. Past that point a layout experiment usually needs real content, not more numbered boxes.