Cap
Lightweight open-source CAPTCHA solution using SHA-256 proof-of-work. 250x smaller than hCaptcha, fully customizable, and privacy-focused with zero telemetry.
Technical Profile & Specs
verified 2026-11-07
- Cost
- $0 / forever (Open Source)
- License
- Open Source
- Hosting Model
- Self-host (your server)
- Platforms
- webself-hosteddocker to self-host
- Installation
- Clone https://github.com/tiagozip/cap or deploy with Docker Compose
- Operational Setup
- Deploy via Docker or binary release from GitHub and configure environment variables.
- Where Your Data Lives
- All application data and configuration live on your own server or local database.
- The Catch / Trade-off
- Requires self-hosting setup, updates, and server maintenance compared to managed Cloudflare Turnstile.
Replaces 3 paid apps
up to $45/mo ($540/yr) in subscriptions
Cap FAQ
Common questions
Is Cap free and open source?+
Cap is an open-source tool licensed under Open Source that runs on self-host. Lightweight open-source CAPTCHA solution using SHA-256 proof-of-work. 250x smaller than hCaptcha, fully customizable, and privacy-focused with zero telemetry.
What paid software does Cap replace?+
Cap serves as a free replacement for 3 paid SaaS applications: Cloudflare Turnstile, hCaptcha, reCAPTCHA, saving up to $45/month ($540/year) in subscription bills.
How do you install and set up Cap?+
Installation: Clone https://github.com/tiagozip/cap or deploy with Docker Compose. Setup notes: Deploy via Docker or binary release from GitHub and configure environment variables.
What is the catch or trade-off with Cap?+
Requires self-hosting setup, updates, and server maintenance compared to managed Cloudflare Turnstile.