Flexbox Playground

What is Flexbox Playground?

Flexbox Playground provides a fully interactive visual editor for CSS Flexbox layout with real-time preview. It exposes all flex container properties (flex-direction, flex-wrap, justify-content, align-items, align-content, gap) and per-item properties (flex-grow, flex-shrink, flex-basis, align-self, order). The tool generates clean CSS output and lets you add, remove, and resize child items to experiment with different layout configurations.

Frontend developers learning Flexbox, UI engineers prototyping responsive layouts, and CSS instructors creating visual demonstrations of flex behavior. The tool runs entirely in your browser — your data never leaves your device.

How to Use Flexbox Playground

1. Set the flex container properties using the control panel — direction, wrapping, and alignment
2. Add child items using the Add Item button and observe how they fill the container
3. Click on individual items to edit their flex-grow, flex-shrink, and flex-basis values
4. Experiment with justify-content and align-items to control spacing and alignment
5. Copy the generated CSS for both the container and child items to use in your project

Common Use Cases

• Learning Flexbox behavior by visually experimenting with container and item properties
• Prototyping navigation bar layouts with flexible spacing between menu items
• Building card grid layouts that wrap responsively without media queries
• Debugging flex item sizing by adjusting grow, shrink, and basis values interactively
• Creating vertically centered layouts — the classic problem Flexbox was designed to solve

Pro Tips

• Use flex: 1 as shorthand for flex-grow: 1, flex-shrink: 1, flex-basis: 0% — this makes items share space equally, which is the most common flex layout pattern
• When items overflow unexpectedly, check flex-shrink — it defaults to 1, meaning items will shrink. Set flex-shrink: 0 on items that should maintain their natural size
• Use gap instead of margins between flex items — gap only adds space between items, not on the outer edges, eliminating the need for negative margin hacks

Why Use This Tool?

• Privacy-first: All processing happens locally in your browser. No data is transmitted to any server.
• No installation required: Works in any modern browser on desktop or mobile.
• Completely free: No account, no credit card, no usage caps.
• Fast and reliable: Powered by modern Web APIs for near-instant results.

Related Concepts

Learn more about related topics: CSS Grid, flex-basis, align-items, justify-content.

Frequently Asked Questions