alternatives to
Google's service that scores or challenges visitors to tell humans from bots. A closed product from Google.
| Tool | Fit | Stars | Licence | Terms | Self-hosted | Language | Latest | Last push |
|---|---|---|---|---|---|---|---|---|
| Cap | Full replacement | 7.9k | Other | Open source | Yes | JavaScript | standalone@3.1.13 | 2026-10-04 |
| ALTCHA | Full replacement | 2.8k | MIT | Open source | Yes | TypeScript | v3.3.0 | 2026-10-05 |
2 alternatives
privacy-first, open-source and self-hosted CAPTCHA alternative with PoW and instrumentation challenges.
Proof-of-work CAPTCHA with a self-hosted server and an invisible mode.
GDPR, WCAG 2.2 AA, and EAA compliant, self-hosted CAPTCHA alternative with PoW mechanism.
Proof-of-work widget verified on your own server, with no cookies or tracking.