# Rotary Knob

> A hardware-style control knob with a brushed-metal body, a ring of ticks that light up with the value, fine-adjust on Shift, keyboard steps, double-click reset and a spring-damped indicator.

- Slug: `rotary-knob`
- Category: [Inputs](https://www.assembli.design/category/inputs.md)
- Type: component
- Tags: knob, dial, slider, audio, tactile
- npm dependencies: motion
- shadcn/ui dependencies: none
- Added: 2026-10-15
- Live preview: https://www.assembli.design/preview/rotary-knob
- Page: https://www.assembli.design/components/rotary-knob

## Install

One-time setup (needs a subscription):

1. Add the registry to the project's `components.json`: `{"@assembli":{"url":"https://www.assembli.design/r/{name}.json","headers":{"Authorization":"Bearer ${ASSEMBLI_API_KEY}"}}}` (merge into `"registries"`).
2. Put an API key from https://www.assembli.design/account in `.env.local` as `ASSEMBLI_API_KEY=asm_…`.

Then install with the shadcn CLI (writes `components/rotary-knob/rotary-knob.tsx` and installs dependencies):

```bash
npx shadcn@latest add @assembli/rotary-knob
```

Registry item JSON: https://www.assembli.design/r/rotary-knob.json (send `Authorization: Bearer <api key>`)

## Code

> Component source needs an Assembli subscription ($12/month) and an API key sent as `Authorization: Bearer <key>`. To get one without copying anything, POST https://www.assembli.design/api/agent/login (or call the MCP tool connect_account), show the user the link it returns, and poll https://www.assembli.design/api/agent/token for the key. Or subscribe at https://www.assembli.design/pricing and create a key at https://www.assembli.design/account.