WhoisAPI VS SubAnalyzer

SubAnalyzer's answer:

Most subdomain finders stop at a list of names. SubAnalyzer finds a domain’s subdomains, then checks every one of them in the same scan: IP addresses, network owner and cloud provider, 58 common ports, screenshots of the web pages, subdomain takeover risk, who can send email as the domain, and other domains the same organization owns. Names come from our own index of certificate transparency logs, plus passive DNS, website links and live DNS lookups. Names that only a wildcard DNS record answers for are left out unless something shows they are real, so the list holds hosts that exist. An AI summary puts urgent findings first: code decides what gets flagged, and the model only words it.

SubAnalyzer's answer:

It runs in the browser with nothing to install, and two domains a day are free without an account, so you get results in minutes instead of setting up command-line tools. One scan replaces several tools: subdomain discovery, port scanning, screenshots, takeover checks and email security, in one table you can search, filter and share. Paid plans cost $15 a month or $150 a year. They re-scan up to 10 domains daily, weekly or monthly and email you when new subdomains, services or takeover risks appear, and every change is kept in the history. Scans come from published addresses, so anyone scanned can see who it was and contact us.

SubAnalyzer's answer:

People responsible for what an organization exposes on the internet: security and IT teams at companies and public bodies who need to know every subdomain they run and hear when something changes, and consultants who check this for clients. It’s also built for pentesters, bug bounty hunters and OSINT researchers doing reconnaissance, and for people getting started in cybersecurity, since the free scans need no account.

SubAnalyzer's answer:

SubAnalyzer was built to make attack surface management accessible to everyone, from security teams to people just getting started in cybersecurity: no setup, just results you can act on. SubAnalyzer 2.0 was rebuilt from the ground up in 2026 to check every subdomain it finds, not just list it: open ports, screenshots, takeover risk and email security. It has its own index of certificate transparency logs, and monitoring emails you when something changes. So far it has scanned more than 42,000 domains and found over 5.6 million subdomains.

SubAnalyzer's answer:

Our stack includes Next.js, React and TypeScript for the web app, with Django (Python) and PostgreSQL powering the API. Our Python scanners use massdns, masscan and Playwright, while our custom certificate transparency index is built in Go. Infrastructure runs on Microsoft Azure Container Apps, AWS Lambda and Cloudflare, with Docker for containerization. We use Anthropic’s Claude to describe screenshots, identify related domains and draft scan summaries, and Stripe to handle billing.

SubAnalyzer's answer:

Security teams, bug bounty hunters and business owners.