An open-source CAPTCHA Box alternative designed with privacy and data protection in mind.

Add the script tag to your HTML file:

<script
	src="https://cdn.jsdelivr.net/npm/librecap@0.3.3/dist/librecap-min.js"
	integrity="sha512-n4+vqAtXwD3NMFNHcF0aPt76W/+vANmhACmI7aGhnJaFD62gkd97zi6qml8PvK8UPCAbRbhEuQoxbl18GM2J+A=="
	crossorigin="anonymous"
></script>

Add a CAPTCHA box to your website by inserting this div wherever you need verification:

<div class="librecap"></div>

That's it! The default configuration works out of the box using your own server implementation that can be found here.

• Quick Start
• Screenshots
• Overview
• Features
• Installation
• Advanced Configuration
• Development
• Browser Compatibility
• Contributing
• License

LibreCap offers a privacy-friendly CAPTCHA solution that respects your users' data. Unlike other CAPTCHA services, LibreCap operates without tracking, cookies, or analytics, making it an excellent choice for websites that prioritize user privacy.

• Privacy-First Design: No tracking, no cookies, no analytics, no third-party services
• Adaptive Theming: Dark, light, and automatic theme support to match your website
• Internationalization: Translations for 107 languages with automatic language detection
• Mobile-Friendly: Works seamlessly on all devices, including mobile
• Customizable: Easily style with CSS to match your website's design
• Dual Verification Methods: Supports both Proof of Work (PoW) and traditional CAPTCHA challenges

git clone https://github.com/librecap/librecap.git
cd librecap
npm install
npm run demo

Add the script tag to your HTML file:

<script
	src="https://cdn.jsdelivr.net/npm/librecap@0.3.3/dist/librecap-min.js"
	integrity="sha512-n4+vqAtXwD3NMFNHcF0aPt76W/+vANmhACmI7aGhnJaFD62gkd97zi6qml8PvK8UPCAbRbhEuQoxbl18GM2J+A=="
	crossorigin="anonymous"
></script>

Add a CAPTCHA box to your website by inserting this div wherever you need verification:

<div class="librecap"></div>

npm install librecap

Then import it in your project:

import 'librecap'

LibreCap can be customized by adding data attributes to your div:

<div class="librecap" data-theme="dark" data-language="en"></div>

Available configuration options:

• data-theme: Set to "light", "dark", or "auto" (default)
• data-language: CURRENTLY ONLY FOR AUDIO CHALLENGE GENERATION; Set a specific language code after ISO 639-1 or "auto" (default)
• data-sitekey: Set your LibreCap site key when using a third party gateway server (optional, only when using a third party gateway server)
• data-endpoint: Set the URL of your LibreCap endpoint, this could be an gateway server or your own server address (default: https://librecap.tn3w.dev/librecap/v1 when an site key is provided, otherwise /librecap/v1)
• data-brand-title: Set the title of the brand (default: "LibreCap")
• data-brand-url: Set the URL of the brand (default: "https://github.com/librecap/librecap")
• data-brand-logo: Set the logo URL of the brand (default: base64 encoded url representation of LibreCap logo)
• data-brand-description: Set the description of the brand (default: "LibreCap is an open-source CAPTCHA alternative designed with privacy and data protection in mind.")
• data-brand-github: Set the GitHub URL of the brand (default: "https://github.com/librecap/librecap")
• data-brand-terms: Set the terms URL of the brand (default: "https://github.com/librecap/librecap/blob/main/TERMS.md")
• data-brand-privacy: Set the privacy URL of the brand (default: "https://github.com/librecap/librecap/blob/main/PRIVACY.md")

Clone the repository:

git clone https://github.com/librecap/librecap.git
cd librecap

Install the dependencies:

npm install

Build the project:

npm run build

Start the demo server:

Install express and cors before running the demo server.

npm install express cors

npm run demo

Contributions are welcome! Please feel free to submit a Pull Request.

1. Fork the project
2. Create your feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add some amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

Copyright 2025 LibreCap Contributors

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.