CSS Grid vs Flexbox: Which One Should You Use

Grid and Flexbox aren’t competitors — they solve different layout problems, and most real interfaces use both together, nested inside each other.

The Simple Rule

• Flexbox — one-dimensional layout: a row of nav items, a column of stacked cards, distributing space along a single axis.
• Grid — two-dimensional layout: an actual page structure with both rows and columns that need to align together.

/* Grid for the overall page structure */
.page {
    display: grid;
    grid-template-columns: 250px 1fr;
}

/* Flexbox for a one-dimensional row within a grid area */
.toolbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

A common tell for which one to reach for: if you find yourself fighting Flexbox’s flex-wrap to approximate a grid, or fighting Grid to center a single row of buttons, you’ve picked the wrong tool for that specific piece — swap it, rather than forcing one tool to do both jobs everywhere.