Modern CSS Layouts with Subgrid

CSS Subgrid has modernised the way designers prepare mockups. Before they came into action, designers struggled to align different elements in their layouts perfectly. For example, on a business website, one testimonial might be a sentence long, another could be a full paragraph. This inconsistency resists complex, responsive designs, often breaking the visual alignment of components in a grid.

CSS Subgrid easily handles these inconsistencies and helps child elements align with their parent elements.

CSS Subgrid acts like a nested grid. It sets the track sizing of subgrid onto the parent grid, thus allowing nested elements to inherit grid tracks and grow to fit the content and maintain consistent alignment.

Limitations of CSS Grid

CSS Grid offers a two-dimensional control over elements in a layout design. However, there is one major limitation: grid tracks apply only to direct children. Which means that any child elements that exist beyond the first level will operate independently without a direct link to their siblings or the parent grid. This is problematic because not being part of the main grid can lead to a disjointed layout, especially in responsive or content-rich designs.

How Does Subgrid Work?

When a designer builds a classic layout, such as a grid with columns for a sidebar, main content, and metadata, subgrids help the inner sections, like author bios or comment threads, to match their alignment without requiring duplicate definitions or CSS codes. The subgrid value enables child elements to inherit row and column tracks with the grid lines of their parent. With subgrid enabled, nested grid containers do not define their own independent layout context, but rather, they reuse the parent’s. This results in greater cohesion and cleaner code.

Here’s a basic example:

.article {
  display: grid;
  grid-template-columns: 2fr 5fr 1fr;
}

.meta {
  display: grid;
  grid-column: 2;
  grid-template-columns: subgrid;
}

In this example, .subgrid inherits the column structure of .grid, enabling its children to align seamlessly with the parent layout. The .meta content slots directly into the parent column structure.

The result is a clean markup, fewer lines, and more scalable CSS for complex layouts.

Subgrid is especially useful in editorial layouts, card grids, or reusable UI components where vertical and horizontal alignment needs to remain consistent across varying content types.

Building a Flexible Layout with Subgrid

Responsiveness is one of the most important factors of a good user experience. As illustrated in the following UX vs. UI infographic, easy navigation and usability define UX, and Subgrid enables developers to achieve this.

It builds scalable, maintainable website architectures without compromising on responsiveness, and it is pretty much evident how adaptable layouts contribute to smoother interactions across different devices and screen sizes.

Let’s say you're designing a three-card product section. Each card contains a heading, description, and a call-to-action button. Some descriptions are short, and some are longer than others.

Every designer has the know-how of basic HTML and CSS code, so we won't dive into that, our focus is on how to add a Subgrid.

Using Subgrid allows all buttons and headings in the product sections to align in their respective rows - even if the content has variable lengths.

Project Objectives

A grid container has three cards.
Each card is a subgrid that inherits row and column tracks.
The layout must remain visually consistent even if there are differences in content.

Here’s the core idea:

Use display: grid and grid-template-rows: subgrid inside each card
Ensure the parent grid defines consistent row heights
This method ensures that every paragraph and button sits in the same row position across cards, creating a cleaner and more professional layout.

CSS Subgrid DevTools

In any modern browser, Subgrid support is built into its DevTools. To inspect it:

Open your layout in the browser.
Right-click and choose Inspect (or use Cmd + Option + I / Ctrl + Shift + I).
Navigate to the Elements panel.
Toggle the subgrid badge next to the element.

This overlay lets you see inherited tracks, named lines, and how the layout adapts to different content lengths.

Browser Support

Subgrid is fully supported in Chrome, Edge and Firefox. Firefox has had these specific-tools for years; Chrome and Edge introduced it in version 115 and above

Subgrid also has experimental support in Safari and Chromium browsers under feature flags. This innovative feature has eliminated the need to hand-tailor layouts to avoid ragged lines and sections. Design systems and component libraries demand perfect consistency, which is why more browsers are adopting this feature.

CSS Subgrid is supported across the following minimum versions of major browsers;

The Future of Subgrid

Subgrid makes complex, modular design systems simple to manage. It was introduced as a part of the CSS Grid Level 2 specification and has now graduated to the Baseline 2023 standard. This means it is officially considered safe and stable for general use.

Subgrid can easily create editorial sections, luxury product showcases, or sophisticated dashboards that stay flexible and look great as well, which is a win for both designers and developers.

Conclusion

CSS Subgrid is an evolution of an old practice where designers had to manually align layouts. Now, the abilities of Subgrid allow developers to maintain perfect alignment and spacing, and make their code cleaner and manageable. It is easy to implement, widely supported across different browsers, and solve nested components inconsistencies with a cleaner approach.

Elise Gibbons @elisegibbons