Compare / ALTCHA vs mCaptcha
ALTCHA vs mCaptcha
Pick ALTCHA if you want the published reCAPTCHA / hCaptcha stack (an MIT proof-of-work widget). Pick mCaptcha if you want that AGPL-3.0 PoW backend.
Facts checked 27 Oct 2026. License, language, and GitHub activity come from the catalog or the project's own repo. "Not in the catalog row" means the public catalog dump does not store that number.
ALTCHA in the catalog mCaptcha in the catalog Start on Railway
How they compare
| ALTCHA | mCaptcha | |
|---|---|---|
| License | MIT License (catalog) source | AGPL-3.0 (catalog) source |
| Language | TypeScript (catalog) | Rust (catalog) |
| GitHub activity | 2,831 stars in the catalog source | 2,493 stars in the catalog source |
| Self-host | A widget plus optional server checks. Official docs at altcha.org. | A PoW backend. Official repo at mCaptcha/mCaptcha. |
| Best for | The published reCAPTCHA / hCaptcha replacement. | An AGPL backend if ALTCHA is not the shape. |
Self-hosting and resource needs
Both are named on the published lander — /stacks/altcha-captcha. ALTCHA is altcha-org/altcha (MIT; 2,831 stars in the catalog). mCaptcha is mCaptcha/mCaptcha (AGPL-3.0; 2,493 stars in the catalog). Cloudflare Turnstile is not open source — this site skips it. Neither has a one-click c17 Railway template.
FAQ
- Is this login?
- Login stays on /replace/clerk. This pair is the bot widget.
- Why not Turnstile?
- Cloudflare Turnstile is not open source. This site skips it.
- Are these free?
- ALTCHA is MIT. mCaptcha is AGPL-3.0. You pay hosting.
- How do I deploy ALTCHA?
- Open /stacks/altcha-captcha. Drop the vendor script. Confirm one submit.
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