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ALTCHA

GDPR compliant, self-hosted CAPTCHA alternative.
README.md

ALTCHA

ALTCHA is free, open-source CAPTCHA alternative that protects your website from spam and abuse.

It uses a proof-of-work mechanism to protect your website, APIs, and online services from spam and unwanted content. Unlike other CAPTCHA solutions, ALTCHA is free, open-source and self-hosted, does not use cookies nor fingerprinting, does not track users, and is fully compliant with GDPR.

Get Started

Refer to the documentation.

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  1. altcha altcha Public

    GDPR, WCAG 2.2 AA, and EAA compliant, self-hosted CAPTCHA alternative with PoW mechanism.

    TypeScript 2.8k 137

  2. altcha-lib altcha-lib Public

    A JavaScript library for creating and verifying ALTCHA challenges.

    TypeScript 105 15

  3. altcha-wordpress-next altcha-wordpress-next Public

    ALTCHA for WordPress v2 is the professional solution for keeping your website safe from spam, bots, and abuse.

    PHP 23 3

Repositories

Showing 10 of 42 repositories
  • altcha-lib-java Public

    A lightweight Java library for creating and verifying ALTCHA challenges.

    altcha-org/altcha-lib-java's past year of commit activity
    Java 24 MIT 4 0 0 Updated Oct 2, 2026
  • altcha-lib-cpp Public

    C++17 library and CLI implementing the ALTCHA Proof-of-Work v2 protocol.

    altcha-org/altcha-lib-cpp's past year of commit activity
    C++ 2 1 0 0 Updated Oct 2, 2026
  • altcha-lib-php Public

    A lightweight PHP library for creating and verifying ALTCHA challenges.

    altcha-org/altcha-lib-php's past year of commit activity
    PHP 113 MIT 12 0 0 Updated Oct 1, 2026
  • altcha-lib-py Public

    A lightweight Python library for creating and verifying ALTCHA challenges.

    altcha-org/altcha-lib-py's past year of commit activity
    Python 33 MIT 8 0 0 Updated Oct 1, 2026
  • sentinel-install-scripts Public
    altcha-org/sentinel-install-scripts's past year of commit activity
    Shell 2 0 0 0 Updated Sep 30, 2026
  • altcha Public

    GDPR, WCAG 2.2 AA, and EAA compliant, self-hosted CAPTCHA alternative with PoW mechanism.

    altcha-org/altcha's past year of commit activity
    TypeScript 2,793 MIT 137 0 0 Updated Sep 30, 2026
  • altcha-lib-go Public

    A Go library for creating and verifying ALTCHA challenges.

    altcha-org/altcha-lib-go's past year of commit activity
    Go 48 MIT 3 0 0 Updated Sep 29, 2026
  • altcha-lib-dotnet Public

    A .NET Library library for creating and verifying ALTCHA challenges.

    altcha-org/altcha-lib-dotnet's past year of commit activity
    C# 1 MIT 0 0 0 Updated Sep 28, 2026
  • helm-charts Public
    altcha-org/helm-charts's past year of commit activity
    Go Template 3 3 0 0 Updated Sep 24, 2026
  • altcha-sentinel-deploy-azure Public
    altcha-org/altcha-sentinel-deploy-azure's past year of commit activity
    0 0 0 0 Updated Sep 24, 2026
View all repositories

People

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