CSS Flexbox & Grid Generator Online Free
Build CSS Flexbox and Grid layouts visually with real-time preview. Adjust all properties with toggles and sliders, then copy the ready-to-use CSS — no signup needed.
How to Use the CSS Layout Generator
- Choose Flexbox or Grid — select your layout model from the top tabs.
- Pick a preset or customize — start with Holy Grail, Card Grid, Nav Bar, or any other preset.
- Adjust the controls — use toggles and sliders to change direction, wrapping, alignment, columns, and gap.
- See the live preview — colored boxes update instantly as you change settings.
- Copy or download — copy the CSS or download it as a
.cssfile.
Features
- ✓ Flexbox and CSS Grid support
- ✓ 7 common layout presets
- ✓ Live colored item preview
- ✓ All justify/align properties covered
- ✓ Custom grid-template-columns string
- ✓ Adjustable gap, items, and row height
- ✓ Copy CSS to clipboard
- ✓ Download as .css file
- ✓ Dark mode friendly
- ✓ Runs entirely in the browser
Quick Flexbox & Grid Reference
Flexbox container properties
display: flex— enable flexboxflex-direction— row, column, reverseflex-wrap— nowrap, wrap, wrap-reversejustify-content— main-axis alignmentalign-items— cross-axis alignmentgap— spacing between items
CSS Grid container properties
display: grid— enable gridgrid-template-columns— column track sizesgrid-auto-rows— implicit row heightscolumn-gap / row-gap— guttersjustify-items— inline alignment per cellalign-items— block alignment per cell
Frequently Asked Questions
When should I use Flexbox vs CSS Grid?
Use Flexbox for one-dimensional layouts — aligning items in a row or column. Use CSS Grid for two-dimensional layouts — placing items in rows AND columns simultaneously. Flexbox is great for navigation bars and card rows; Grid excels at full-page layouts.
What is justify-content in Flexbox?
justify-content controls how flex items are distributed along the main axis (horizontally in row direction). Options include flex-start, center, flex-end, space-between, space-around, and space-evenly.
What does 1fr mean in CSS Grid?
1fr stands for one fraction of available space. grid-template-columns: repeat(3, 1fr) creates three equal-width columns that share the container width. You can mix fractions with fixed sizes: 200px 1fr 200px gives a fixed sidebar with a flexible center column.
What is the Holy Grail layout?
The Holy Grail layout is a classic web layout with a header, footer, main content area, and two sidebars — all in a three-column grid. It was historically difficult to achieve with CSS floats but is simple with CSS Grid: grid-template-columns: 200px 1fr 200px.
How do I make a responsive grid?
Use auto-fill or auto-fit with minmax(): grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)). This creates as many columns as fit while keeping each at least 280px wide. No media queries needed for basic responsiveness.
Can I download the generated CSS?
Yes. Click the "Download .css" button below the CSS output to save the generated stylesheet as a .css file ready to include in your project.