When should I use Flexbox versus CSS Grid?

Flexbox excels at one-dimensional layouts — distributing items along a single row or column. Grid is designed for two-dimensional layouts where you control both rows and columns simultaneously. In practice, many UIs use both.

Does the generated CSS work in all modern browsers?

Yes. Flexbox and Grid are fully supported in all modern browsers. No vendor prefixes are needed for standard properties in browsers released after 2020.

How do I center an element with Flexbox?

On the flex container, set display: flex, justify-content: center, and align-items: center. This centers the child both horizontally and vertically.

Design CSS Flexbox Layouts Online

CSS Flexbox and Grid are the two most powerful layout systems in modern web development, but their many properties and values can be confusing to reason about without seeing the result. Should you use align-items or align-content? When does justify-self apply versus justify-items? devtoolkit.sh's Flexbox Generator lets you click through every flex container and flex item property — direction, wrapping, alignment, gaps — and see the layout render in real time before you write a single line of code. The Grid Generator provides the same visual approach for CSS Grid, letting you define rows, columns, and template areas interactively. Both tools output clean, minimal CSS that you can paste directly into your stylesheet. This workflow is far faster than the trial-and-error cycle of writing CSS, saving, and refreshing — especially when you are exploring layout options or explaining a concept to a teammate.

<->CSS Flexbox Generator

Interactive CSS flexbox playground with live preview and copyable CSS code.

[#]CSS Grid Generator

Interactive CSS grid playground with live preview and copyable CSS code.

FAQ

When should I use Flexbox versus CSS Grid?: Flexbox excels at one-dimensional layouts — distributing items along a single row or column. Grid is designed for two-dimensional layouts where you control both rows and columns simultaneously. In practice, many UIs use both.
Does the generated CSS work in all modern browsers?: Yes. Flexbox and Grid are fully supported in all modern browsers. No vendor prefixes are needed for standard properties in browsers released after 2020.
How do I center an element with Flexbox?: On the flex container, set display: flex, justify-content: center, and align-items: center. This centers the child both horizontally and vertically.