WebDecoy/FCaptcha

Detect bots, vision AI agents, and headless browsers through 40+ behavioral signals and SHA-256 proof of work. Self-hosted, privacy-first, and fully open source.

47
/ 100
Emerging

FCaptcha helps website owners protect their online forms and interactions from malicious automated traffic, including traditional bots, advanced AI agents, and credential stuffing attacks. It takes in user interaction data and environmental signals from your website, processing them to output a score that indicates whether the user is human or a bot, allowing you to block or challenge suspicious activity. Website administrators, e-commerce managers, and online service providers looking to secure their platforms from automated threats would use this.

119 stars. Available on npm.

Use this if you need a self-hosted, privacy-focused CAPTCHA solution that can detect sophisticated bots and AI without relying on external services.

Not ideal if you prefer a fully managed CAPTCHA service and do not want to handle server deployment or infrastructure for bot detection.

website-security bot-prevention fraud-detection credential-stuffing-protection online-form-security
Maintenance 10 / 25
Adoption 10 / 25
Maturity 22 / 25
Community 5 / 25

How are scores calculated?

Stars

119

Forks

3

Language

JavaScript

License

MIT

Last pushed

Mar 02, 2026

Commits (30d)

0

Dependencies

3

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curl "https://pt-edge.onrender.com/api/v1/quality/perception/WebDecoy/FCaptcha"

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