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Cap

Lightweight open-source CAPTCHA solution using SHA-256 proof-of-work. 250x smaller than hCaptcha, fully customizable, and privacy-focused with zero telemetry.

Open Source Alternative to:

Screenshot of the Cap website

 
8,236stars+312(+3.9%)

Last 30 days

Self-host in 3 steps
  1. 1

    Start a KVM 2 VPS on Hostinger

    Recommended plan for one-click apps.

  2. 2

    Apply code

    10% off any 12-month plan at checkout.

  3. 3

    Deploy Cap

    With Hostinger's one-click installer.

Host with Hostinger

Cap offers a revolutionary approach to web security with its privacy-first CAPTCHA alternative that eliminates the need for visual puzzles. Using SHA-256 proof-of-work technology, it provides robust protection while respecting user privacy.

Key advantages:

  • Ultra-lightweight: At just ~20kb with zero dependencies, it's 250x smaller than hCaptcha and loads in milliseconds
  • Complete privacy: No telemetry sent to external servers, keeping user data secure
  • Fully customizable: Modify colors, size, position, and icons using CSS variables to match your brand
  • Modern approach: Users solve computational challenges instead of time-consuming visual puzzles

Flexible deployment options:

  • Self-hosted: Full control over your CAPTCHA implementation
  • Standalone mode: Deploy anywhere using Docker containers with built-in analytics
  • Programmatic integration: Hide widgets and solve challenges in the background
  • API protection: M2M capabilities keep APIs secure while remaining accessible to authorized bots

Built with developers in mind, Cap is completely open-source under the Apache 2.0 license and can replace reCAPTCHA in minutes. The European-built solution prioritizes user experience without compromising security.

Share:

8,236stars+312(+3.9%)

Last 30 days

Self-host in 3 steps
  1. 1

    Start a KVM 2 VPS on Hostinger

    Recommended plan for one-click apps.

  2. 2

    Apply code

    10% off any 12-month plan at checkout.

  3. 3

    Deploy Cap

    With Hostinger's one-click installer.

Host with Hostinger

 
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