Curated
Friendly Captcha
Invisible, privacy-friendly CAPTCHA that uses proof-of-work
Network DefensePrivacy first CAPTCHA
Alternatives to ALTCHA
12 tools like ALTCHA, chosen by what they do. About ALTCHA
Open source
mCaptcha
Open source proof-of-work CAPTCHA that does not track users
Network DefenseOpen source PoW CAPTCHAInactive
Freemium
hCaptcha
Privacy-focused CAPTCHA and bot detection for sites and apps
Network DefensePrivacy focused CAPTCHA
Open source
Headscale
Self-hosted, open source server for a Tailscale network
Network DefenseSelf hosted Tailscale server
Open source
OWASP Coraza
Go-based open source web application firewall with CRS support
Network DefenseGo web application firewall
Open source
ModSecurity
Open source web application firewall engine used with OWASP rules
Network DefenseOpen source WAF engine
Open source
Proton VPN
VPN with a free plan, open source apps and a no-logs audit
Network DefenseSwiss privacy VPN
Freemium
Paid
Sucuri
Website security service for malware cleanup and firewall
Network DefenseWebsite firewall and cleanup
Open source
NetBird
Open source zero trust network access built on WireGuard
Network DefenseOpen source zero trust network
Curated
