# cap — modern, lightning-quick PoW captcha cap is a lightweight, modern open-source CAPTCHA alternative designed using SHA-256 PoW. | [documentation →](https://capjs.js.org) | [demo](https://cap-starter.glitch.me) |----------|----------| [![npm @cap.js/server](https://img.shields.io/badge/@cap.js/-server-CB0200?logo=npm)](https://www.npmjs.com/package/@cap.js/server) [![npm @cap.js/widget](https://img.shields.io/badge/@cap.js/-widget-CB0200?logo=npm)](https://www.npmjs.com/package/@cap.js/widget) [![npm @cap.js/solver](https://img.shields.io/badge/@cap.js/-solver-CB0200?logo=npm)](https://www.npmjs.com/package/@cap.js/solver) [![OpenSSF Best Practices](https://www.bestpractices.dev/projects/9920/badge)](https://www.bestpractices.dev/projects/9920)

## why Cap? - ⚡️ **250x smaller than hCaptcha** cap's widget library is extremely small, only 12kb minified and brotli'd. - 🔒️ **Private** cap's usage of proof-of-work eliminates the need for any tracking, fingerprinting or data collection. - 🌈 **Fully customizable** cap is self-hostable so you can customize both the backend & frontend — or you can just use CSS variables - 🤖 **PoW-based** cap uses proof-of-work instead of complex puzzles, making it easier for humans and harder for bots - 🧩 **Standalone mode** cap offers a standalone mode with Docker, allowing you to use it with languages other than JS. - 💨 **Invisible mode** cap can run invisibly in the background using a simple JS API. - ☁️ **Floating mode** floating mode keeps your CAPTCHA hidden until it's needed - 🌳 **Fully FOSS** completely open source under the Apache license 2.0 license ## star history [![Star History Chart](https://api.star-history.com/svg?repos=tiagorangel1/cap&type=Date)](https://www.star-history.com/#tiagorangel1/cap&Date) ***