altdns vs ZoomEye: Side-by-Side Comparison (2026)
Features, pricing, ratings, and pros & cons — compared head-to-head.
altdns is a free external attack surface management tool. ZoomEye is a free external attack surface management tool. Compare features, ratings, integrations, and community reviews side by side to find the best external attack surface management fit for your security stack.
CST VerdictBased on our analysis of available product data, here is our conclusion:
Security teams hunting for overlooked subdomains in external attack surface reconnaissance will find altdns invaluable because it generates permutations that standard enumeration tools miss, catching typosquatting and subdomain variations that land in your blind spots. The 2,439 GitHub stars reflect adoption by practitioners who've validated the mutation logic against real-world domain configurations. Skip this if you need a managed UI or integration with your existing EASM platform; altdns is a CLI-first tool that demands operator familiarity and manual orchestration into your scanning workflow.
Security teams conducting external attack surface discovery on a budget will get the most from ZoomEye; its free tier gives you real-time visibility into exposed assets and service versions across your internet-facing infrastructure without licensing friction. The search engine indexes over 600 million IP addresses and devices, letting you identify vulnerabilities before an attacker does. Skip this if you need continuous posture monitoring or remediation workflows; ZoomEye is a reconnaissance tool, not a management platform.
