CSS Flexbox Generator

About CSS Flexbox Generator

CSS Flexbox (Flexible Box Layout) is one of the most powerful layout systems in modern CSS. It provides an efficient way to distribute space among items in a container and align them in flexible, responsive ways — even when their sizes are unknown or dynamic. This visual generator lets you experiment with all Flexbox properties and see the results in real time, then copy the generated CSS code directly into your project.

Flexbox works on two axes: the main axis (defined by flex-direction) and the cross axis (perpendicular to the main axis). Understanding these axes is key to mastering Flexbox. The justify-content property controls alignment along the main axis, while align-items controls alignment along the cross axis. This tool visualizes both axes so you can see exactly how each property affects your layout.

Container vs Item Properties

Flexbox properties are split between the container (parent) and items (children). Container properties like flex-direction, justify-content, align-items, flex-wrap, and gap define the overall layout behavior. Item properties like flex-grow, flex-shrink, flex-basis, order, and align-self let individual items override or customize their positioning within the container. Click on any item in the preview to adjust its individual properties.

Common Flexbox Patterns

Center an element both horizontally and vertically using justify-content: center and align-items: center. Create equal-width columns with flex-grow: 1 on each item. Build a sticky footer with flex-grow: 1 on the main content area. Create responsive navigation bars that wrap on small screens using flex-wrap: wrap. These are just a few of the countless layout patterns that Flexbox makes simple.

FAQ

Q: When should I use Flexbox vs CSS Grid?
A: Flexbox is best for one-dimensional layouts — aligning items in a single row or column. CSS Grid excels at two-dimensional layouts with both rows and columns. Use Flexbox for navigation bars, card rows, form layouts, and centering elements. Use Grid for page-level layouts, dashboards, and complex grid structures. They work great together.

Q: What does flex: 1 mean?
A: The shorthand flex: 1 equals flex-grow: 1, flex-shrink: 1, flex-basis: 0%. It tells the item to grow and fill available space equally with other flex: 1 items. This is the most common way to create equal-width flexible columns.

Q: Why aren't my items wrapping?
A: By default, flex-wrap is set to nowrap, meaning items will shrink to fit on one line rather than wrap. Set flex-wrap to wrap to allow items to flow onto multiple lines when the container is too narrow.

Q: How does the gap property work with Flexbox?
A: The gap property adds consistent spacing between flex items without affecting the outer edges. It is supported in all modern browsers and replaces the older pattern of using margins with negative margins on the container.