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Try gptBuster for comprehensive, self-hosted spam protection.
GDPR compliant Captcha GDPR compliant Captcha

Free, open-source
Captcha alternative

GPTBUSTER uses a proof-of-work mechanism to protect your website, APIs, and online services from spam and unwanted content.

Unlike other solutions, gptBuster is free, open-source and self-hosted, does not use cookies nor fingerprinting, does not track users, and is compliant with data-privacy regulations and accessible.

Need more protection?

Self-hosted spam protection for websites, apps, and services.

gptBuster is a next-generation security system that stops bots and automated threats — without frustrating real users. It intelligently adapts to risks, blending advanced detection with seamless verification to keep your apps and services protected.

AWS

Azure

Kubernetes

Docker

More than just
a Captcha protection

GPTBUSTER represents a modern, accessible, and inclusive approach to safeguarding websites, APIs, and online services from spam and abuse.

Its fundamentally different approach makes it ideal for businesses constrained by privacy regulations in the EU and around the world.

Compliant with Regulations

Comply with GDPR/HIPAA/CCPA/LGPD/DPDPA/PIPL by using a privacy-first solution that does not use cookies nor fingerprinting and does not track users. Learn more.

Complete Spam Protection

Utilize the proof-of-work mechanism as the initial line of defense. Then, stop even sophisticated attacks and human-generated spam with gptBuster.

Friendly to Humans

Say goodbye to tedious puzzle-solving and improve your website's UX by integrating a fully automated proof-or-work mechanism. Try demo.

Inclusive to Robots

Get ready for AIs and integrate M2M GPTBUSTER into your APIs and online services making them accessible to machines. See how.

Open source, MIT licensed

gptBuster is a free, open-source project licensed under a permissive MIT license. Works for everyone - individuals, small businesses and enterprises. Visit GitHub.

Are you a human?

Try Captcha verification for humans

gptBuster's web component is familiar to users and easy to integrate into any website.

Check the box to get verified.

Protected form

This is just a demo. Your message won't be submitted anywhere.

Are you a robot?

Try Machine-to-Machine (M2M) GPTBUSTER

M2M GPTBUSTER works as a rate-limiter implemented on the consumer’s end. It helps you protect expensive resources, reduce spam and abuse in your online services and APIs while keeping them accessible to automated systems.

Read more about M2M GPTBUSTER

Easy integration

For integration, follow the documentation.

Examples

See example setups of GPTBUSTER with different front-end frameworks:

Official Libraries

gptBuster's TypeScript library runs everywhere! Whether it’s modern browsers, Node.js, Bun, Deno, or any WinterCG-compatible runtime.

Plugins

Visit the Integrations documentation for more community-developed libraries and plugins.

gptBuster vs Open Source

gptBuster is an advanced system that adds an extra layer of protection on top of the core open-source functionality. While the open-source version provides basic protection using a proof-of-work mechanism, Sentinel delivers enhanced security and additional features.

gptBuster Open Source
Data Privacy

Compliant with data-privacy regulations.

Accessibility

Fully accessible interface following WCAG guidelines.

Self-hosted

Fully self-hosted on your own infrastructure without external services.

Ready-to-use

All-in-one Docker image with easy deployment options.

Adaptive Captcha

Frictionless experience with extra verification for flagged users.

Text Classifier

Built-in text classifier powered by machine learning.

Training Data

Uses machine learning datasets to improve spam detection.

Language Detection

Identifies and filters content based on detected languages.

Bot Detection

Detect and block bots, crawlers, and AI agents.

IP Reputation

Resolve IP addresses and detect proxies, TOR networks and malicious actors.

IP Geo Fencing

Restrict or allow access based on geographic location.

Email Verification

Verify email addresses and prevent fake sign-ups.

Rate Limiter

Protect against brute force attacks with request rate limiting.

Form Submissions

Built-in form capture API with spam filtering.

Explore the features and documentation of gptBuster for more information.

Copyright © 2024 gptbuster.com - Dedicated to Privacy.

GPTBUSTER ® is a trademark registered in EU.

Project sponsored by BAUSW.com - Digital Construction Site Diary, promoting transparency and trust in construction projects with real-time documentation.

OSS hosted on GitHub • Website made with Astro Starlight.

Do you like GPTBUSTER?
Support us by giving us a star on GitHub!

gptBuster is made in Europe.
Element 1
Hosted by Hetzner, Germany.
CDN by bunny.net, Slovenia.
Servers powered by
green energy.