Deploy Cap in one click installation.
Privacy-first open-source CAPTCHA alternative using proof-of-work instead of visual puzzles — no tracking, no cookies, no external calls.
What you can build with Cap
Cap is a lightweight open-source CAPTCHA alternative that protects forms and APIs from bots using proof-of-work rather than visual puzzles. Instead of asking users to identify traffic lights or crosswalks, Cap runs a silent SHA-256 challenge in WebAssembly — solving in milliseconds for real users while making automated submission computationally expensive for bots. No cookies are set, no behavioral data is collected, and no requests leave your own server.
Self-hosting Cap on your own VPS gives you full control over your bot protection with no per-verification fees and no dependency on services like Google reCAPTCHA or Cloudflare Turnstile. An admin dashboard provides challenge analytics and site key management.
Key features of Cap
Proof-of-Work Challenges
SHA-256 computation runs silently in WebAssembly, making bot protection invisible to real users while raising the cost of automated attacks.
Zero Tracking
No cookies are set, no behavioral fingerprints collected, and no data is sent to third-party servers — fully GDPR-friendly by design.
Admin Dashboard
Monitor challenge completion rates, manage site keys, and review bot activity metrics through the built-in analytics dashboard.
Lightweight Widget
The client-side widget is only ~20KB, adding negligible page weight to any site or application that embeds it.
API-First Design
Verify challenge tokens server-side via a simple REST API, making Cap integrable with any language or framework.
Why run Cap on Hostinger
Launch in one click
Get your application up and running instantly with a preconfigured setup. No manual installation or complex setup steps.
Security you can rely on
Keep your applications protected with a built-in firewall, DDoS protection, and continuous monitoring.
Built in Docker manager
Run and manage multiple Docker containers from one place. Deploy, update, and monitor your projects with ease.
Launch in one click
Get your application up and running instantly with a preconfigured setup. No manual installation or complex setup steps.
Security you can rely on
Keep your applications protected with a built-in firewall, DDoS protection, and continuous monitoring.
Built in Docker manager
Run and manage multiple Docker containers from one place. Deploy, update, and monitor your projects with ease.
Docker VPS hosting you can rely on
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