"Should I use Flexbox or Grid?" is one of the most common CSS questions. Here is the rule I use.

Flexbox is for one direction. Grid is for two.

Use Flexbox for a row or column of items

Navigation bars, button groups, centering one thing:

.nav { display: flex; gap: 1rem; align-items: center; justify-content: space-between; }

The items decide how much space they take, and the container lines them up.

Use Grid for rows and columns together

Card layouts, page layouts, galleries:

.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 1.5rem; }

This one rule gives you a responsive layout with no media queries. The number of columns changes as the screen gets narrower.

Combine them

A common pattern is Grid for the page and Flexbox inside each piece:

.card { display: flex; flex-direction: column; justify-content: space-between; }

That keeps the buttons at the bottom of every card, even when the text lengths differ.

Quick check

  • Laying things out along one line? Flexbox.
  • Need to control rows and columns? Grid.
  • Not sure? Start with Grid, and use Flexbox for the small parts.

Which one do you reach for first? Tell me in the comments.