# Clipboard Activity Detector

> A live demo of how much a web page can tell about your clipboard — and how it knows.

An open demo that detects every copy, cut, paste and drag-drop on a page, infers how each paste was triggered, and logs it — from a single document-level listener.

## Pages

- [Clipboard Activity Detector — Copy, Cut, Paste & Drop](https://cp-detection.vercel.app/): The playground: type, paste and drag into ordinary fields and watch each event get detected and attributed.
- [Events log — Clipboard Activity Detector](https://cp-detection.vercel.app/events): The log of detected events, with the browser session and the server record side by side.

## Key facts

- Detection is one document-level listener in the capture phase, not a handler per input, so it also catches pastes into third-party widgets and components that stop propagation.
- No browser API reports whether a paste came from Ctrl+V, the right-click menu or a drag. This project infers it from event timing.
- During copy and cut the event clipboard data is write-only, so character counts are taken from the selection instead.
- Clipboard text is never sent to the server unless explicitly enabled, and is capped at 80 characters when it is.
- Built with TanStack Start, React 19 and Tailwind. Open source, free to use.