About

ALTCHA is a privacy-first, free, and open-source solution originating from Czechia, designed to help developers and website owners combat bots, spam, and automated abuse. It replaces traditional CAPTCHA systems with a smarter, quieter approach to verification and threat detection, positioning itself as an alternative to services like hCaptcha and reCAPTCHA. Key features include being privacy-focused, lightweight, a spam filter, dark mode, no tracking, GDPR compliant, integrated spam protection, RTL support, multiple languages, and bot detection, leveraging technologies such as Svelte, webcomponents, and audio/code captchas. Available as both Self-Hosted and Software as a Service (SaaS), ALTCHA maintains an active presence on GitHub (github.com/altcha-org/altcha) and Twitter (twitter.com/alternativeto). While its core mission is to stop bots, a user review notes that it may function more as a rate limiter rather than a complete bot deterrent.