# Theme Switch

> A cookie-backed light/dark/auto theme picker with segmented, select or icon-menu variants, that sets a data attribute on the html element and syncs across every switch on the page.

- Author: [zweiundeins](https://21st.dev/@zweiundeins)
- Library: zweiundeins
- License: MIT
- Tags: Dark, Theme Toggle, Segmented Control
- Live preview: https://21st.dev/@zweiundeins/components/theme-switch

## Install

```bash
npx shadcn@latest add "https://21st.dev/r/zweiundeins/theme-switch?api_key=$API_KEY_21ST"
```

Requires a 21st API key (generate one at https://21st.dev/mcp) passed as `API_KEY_21ST`. Free accounts get a limited number of installs per day; unlimited on a paid plan — see https://21st.dev/pricing.

Full component directory: https://21st.dev/llms.txt · More like this: https://21st.dev/community/components/s/dark.md