# Aspect ratio

Keeps width and height in proportion, like 16/9.

## What does `aspect-ratio` do?

`aspect-ratio` keeps an element's width and height in proportion, like 16:9 for videos.

```css
.video-thumb { width: 100%; aspect-ratio: 16 / 9; }
```

Level: Freelancer · [More CSS terms at this level](https://www.ask-codey.com/glossary/subjects/css/freelancer)

Updated: September 27, 2026

Source: https://www.ask-codey.com/glossary/aspect-ratio