# Cap: Free Open Source Alternative to Cloudflare Turnstile, hCaptcha, reCAPTCHA

Canonical: https://caniforkit.com/fork/capjs
Last updated: 2026-11-07

Cap (Open Source, Open Source) replaces Cloudflare Turnstile, hCaptcha, reCAPTCHA. Lightweight open-source CAPTCHA solution using SHA-256 proof-of-work. 250x smaller than hCaptcha, fully customizable, and privacy-focused with zero telemetry.

## Tool Specifications
- **Tool Name**: Cap
- **Type**: Open Source Project
- **License**: Open Source
- **Official Website**: https://capjs.js.org/
- **GitHub Repository**: https://github.com/tiagozip/cap
- **GitHub Stars**: ★ 8.3k
- **Runs On**: Self-host
- **Maintenance Status**: nov 2026
- **Platforms**: web, self-hosted, docker to self-host
- **Data Storage**: All application data and configuration live on your own server or local database.
- **Installation**: Clone https://github.com/tiagozip/cap or deploy with Docker Compose
- **Setup Requirements**: Deploy via Docker or binary release from GitHub and configure environment variables.
- **The Catch / Limitation**: Requires self-hosting setup, updates, and server maintenance compared to managed Cloudflare Turnstile.

## Paid SaaS Applications Replaced (3)
Replacing these paid tools with Cap saves up to $45/mo ($540/yr) in software subscriptions:

| Replaced Software | Category | SaaS Price | Comparison Guide |
| --- | --- | --- | --- |
| [Cloudflare Turnstile](https://caniforkit.com/cloudflare-turnstile) | [automation](https://caniforkit.com/category/automation) | $15/mo | [Compare Cloudflare Turnstile vs Cap](https://caniforkit.com/vs/cloudflare-turnstile-vs-capjs) |
| [hCaptcha](https://caniforkit.com/hcaptcha) | [automation](https://caniforkit.com/category/automation) | $15/mo | [Compare hCaptcha vs Cap](https://caniforkit.com/vs/hcaptcha-vs-capjs) |
| [reCAPTCHA](https://caniforkit.com/recaptcha) | [automation](https://caniforkit.com/category/automation) | $15/mo | [Compare reCAPTCHA vs Cap](https://caniforkit.com/vs/recaptcha-vs-capjs) |

## Frequently Asked 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 is the trade-off or limitation of using Cap?
Requires self-hosting setup, updates, and server maintenance compared to managed Cloudflare Turnstile.

## Related

- [Self-Hosted Open Source Directory](https://caniforkit.com/self-hosted)
- [All Paid SaaS Alternatives Index](https://caniforkit.com/alternatives)
- [Software Categories Directory](https://caniforkit.com/categories)
- [Homepage](https://caniforkit.com)