# Opacity

Makes an element see-through, from 0 to 1.

## What does `opacity` do?

`opacity` makes an element and everything inside it see-through, from `0` (invisible) to `1` (solid).

```css
.sold-out { opacity: 0.4; }
```

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

Updated: September 27, 2026

Source: https://www.ask-codey.com/glossary/opacity