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Open-source projects tagged “Proof Of Work”.

Inspect repositories, licenses, activity, and alternatives across the Proof Of Work ecosystem.

6 projects connectedTag matches come from repository topics and catalog metadata.
Cap
License not declared

Free, open-source and self-hosted CAPTCHA alternative to reCAPTCHA. Privacy-first and powered by proof-of-work and instrumentation challenges.

Security & PrivacyOpen-source projects grouped in this category for discovery and comparison.5 projects#JavaScriptProjects tagged with this topic in the verified catalog.6 projectsGithub ActionsProjects tagged with this topic in the verified catalog.6 projectsNodeJSProjects tagged with this topic in the verified catalog.6 projectsSelf-hostedThis project carries a self-hosting or local-deployment signal. Verify the official install guide before production use.4 self-hosted optionsreCAPTCHAProprietary product with documented open-source alternatives cataloged on OpenSourceChoice. Compare licenses, reposit…6 alternatives
Metrics syncingMetrics syncingStar momentum for this project has not landed in the latest GitHub metrics sync yet. Check trending for repositories with recorded momentum.Browse trending →
FreePricingFree and open sourceFree7.3K49914 days ago
Alternatives toreCAPTCHAreCAPTCHAProprietary product with documented open-source alternatives cataloged on OpenSourceChoice. Compare licenses, reposit…6 alternatives+2
ALTCHA
MIT

GDPR, WCAG 2.2 AA, and EAA compliant, self-hosted CAPTCHA alternative with PoW mechanism.

InfrastructureOpen-source projects grouped in this category for discovery and comparison.1 project#TypeScriptProjects tagged with this topic in the verified catalog.3 projectsGithub ActionsProjects tagged with this topic in the verified catalog.6 projectsJavaScriptProjects tagged with this topic in the verified catalog.6 projectsSelf-hostedThis project carries a self-hosting or local-deployment signal. Verify the official install guide before production use.4 self-hosted optionsreCAPTCHAProprietary product with documented open-source alternatives cataloged on OpenSourceChoice. Compare licenses, reposit…6 alternatives
Metrics syncingMetrics syncingStar momentum for this project has not landed in the latest GitHub metrics sync yet. Check trending for repositories with recorded momentum.Browse trending →
FreePricingFree and open sourceFree2.6K1265 days ago
Alternatives toreCAPTCHAreCAPTCHAProprietary product with documented open-source alternatives cataloged on OpenSourceChoice. Compare licenses, reposit…6 alternatives+2
mCaptcha
AGPL-3.0

A no-nonsense CAPTCHA system with seamless UX | Backend component

Security & PrivacyOpen-source projects grouped in this category for discovery and comparison.5 projects#RustProjects tagged with this topic in the verified catalog.1 projectGithub ActionsProjects tagged with this topic in the verified catalog.6 projectsJavaScriptProjects tagged with this topic in the verified catalog.6 projectsSelf-hostedThis project carries a self-hosting or local-deployment signal. Verify the official install guide before production use.4 self-hosted optionsreCAPTCHAProprietary product with documented open-source alternatives cataloged on OpenSourceChoice. Compare licenses, reposit…6 alternatives
Metrics syncingMetrics syncingStar momentum for this project has not landed in the latest GitHub metrics sync yet. Check trending for repositories with recorded momentum.Browse trending →
FreePricingFree and open sourceFree2.5K949 months ago
Alternatives toreCAPTCHAreCAPTCHAProprietary product with documented open-source alternatives cataloged on OpenSourceChoice. Compare licenses, reposit…6 alternatives+2
Procaptcha
Apache-2.0

Open-source, frictionless CAPTCHA and bot defense. A privacy-focused alternative to reCAPTCHA and hCaptcha.

Security & PrivacyOpen-source projects grouped in this category for discovery and comparison.5 projects#TypeScriptProjects tagged with this topic in the verified catalog.3 projectsGithub ActionsProjects tagged with this topic in the verified catalog.6 projectsJavaScriptProjects tagged with this topic in the verified catalog.6 projectsreCAPTCHAProprietary product with documented open-source alternatives cataloged on OpenSourceChoice. Compare licenses, reposit…6 alternatives
Metrics syncingMetrics syncingStar momentum for this project has not landed in the latest GitHub metrics sync yet. Check trending for repositories with recorded momentum.Browse trending →
FreePricingFree and open sourceFree2989Jul 15, 2026
Alternatives toreCAPTCHAreCAPTCHAProprietary product with documented open-source alternatives cataloged on OpenSourceChoice. Compare licenses, reposit…6 alternatives+2
PrivateCaptcha
License not declared

Independent, privacy-first, self-hostable PoW CAPTCHA service made in EU

Security & PrivacyOpen-source projects grouped in this category for discovery and comparison.5 projects#GoProjects tagged with this topic in the verified catalog.1 projectGithub ActionsProjects tagged with this topic in the verified catalog.6 projectsJavaScriptProjects tagged with this topic in the verified catalog.6 projectsSelf-hostedThis project carries a self-hosting or local-deployment signal. Verify the official install guide before production use.4 self-hosted optionsreCAPTCHAProprietary product with documented open-source alternatives cataloged on OpenSourceChoice. Compare licenses, reposit…6 alternatives
Metrics syncingMetrics syncingStar momentum for this project has not landed in the latest GitHub metrics sync yet. Check trending for repositories with recorded momentum.Browse trending →
FreePricingFree and open sourceFree1826Jul 15, 2026
Alternatives toreCAPTCHAreCAPTCHAProprietary product with documented open-source alternatives cataloged on OpenSourceChoice. Compare licenses, reposit…6 alternatives+2
Friendly Captcha
MPL-2.0

The SDK that is used to integrate Friendly Captcha v2 into your website. Protect your websites and online services from spam and abuse with Friendly Captcha, the privacy-first anti-bot solution.

Security & PrivacyOpen-source projects grouped in this category for discovery and comparison.5 projects#TypeScriptProjects tagged with this topic in the verified catalog.3 projectsGithub ActionsProjects tagged with this topic in the verified catalog.6 projectsJavaScriptProjects tagged with this topic in the verified catalog.6 projectsreCAPTCHAProprietary product with documented open-source alternatives cataloged on OpenSourceChoice. Compare licenses, reposit…6 alternatives
Metrics syncingMetrics syncingStar momentum for this project has not landed in the latest GitHub metrics sync yet. Check trending for repositories with recorded momentum.Browse trending →
FreePricingFree and open sourceFree2814Jul 9, 2026
Alternatives toreCAPTCHAreCAPTCHAProprietary product with documented open-source alternatives cataloged on OpenSourceChoice. Compare licenses, reposit…6 alternatives+2
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