Overview:
Private Captcha is an open-source, self-hostable Proof-of-Work CAPTCHA service developed in the EU. It is designed to combat bots, including AI scrapers, and spam without relying on user behavior tracking or processing personally identifiable information (PII). The project focuses on privacy and GDPR compliance, offering an on-premises deployment alternative to services like Google reCAPTCHA, hCaptcha, and CloudFlare Turnstile. It provides a stable API and lightweight integrations for website owners.
Core Features:
Adaptive challenge difficulty: Adjusts puzzle complexity based on configurable options to counter evolving threats.
Lightweight, customizable widget: Includes an "invisible" version that does not disrupt the user experience.
Self-hostable backend: Designed for on-premises deployment with low resource requirements.
Usage statistics: Provides backend analytics on CAPTCHA performance and traffic.
Privacy-focused design: No behavior tracking or collection of personal identifiable information (PII).
Stable, backward-compatible API: Offers a reliable integration path for developers.
Use Cases:
Website owners seeking privacy-compliant bot protection: Replaces third-party CAPTCHA services that may collect user data, particularly for sites serving EU visitors.
Developers integrating a self-hosted CAPTCHA: Need a lightweight, API-driven service that can run on own infrastructure without external dependencies.
Sites facing AI scraper and spam attacks: Leverages Proof-of-Work to block automated access while maintaining accessibility for real users.
Why It Matters:
Private Captcha is a fully self-hostable alternative to services like Google reCAPTCHA, hCaptcha, and CloudFlare Turnstile. Its open-source nature allows operators to retain full control over CAPTCHA data and avoid reliance on third-party tracking. The backend is optimized for low resource consumption and supports adaptive difficulty scaling, making it suitable for production deployment. It also offers a managed/SaaS version to support project sustainability.
