quien is a terminal-based domain intelligence toolkit that provides an interactive TUI for investigating domains and IP addresses.
It brings together WHOIS/RDAP data, DNS records, mail configuration, SSL/TLS details, HTTP headers, SEO checks, and technology stack detection in a single command-line tool.
This is free and open source software.
Key Features
- Uses RDAP-first lookups with WHOIS fallback and IANA referral for automatic WHOIS server discovery.
- Performs IP lookups with reverse DNS, network information, abuse contacts, ASN discovery, BGP fallback, and PeeringDB enrichment.
- Audits mail configuration including MX, SPF, DMARC, DKIM, and BIMI records.
- Analyses SEO signals including robots.txt, canonical URLs, sitemaps, headings, structured data, Open Graph, Twitter Cards, compression, caching, and render-blocking resources.
- Supports optional Core Web Vitals field data using the Chrome UX Report API.
- Detects technologies including WordPress plugins, JavaScript and CSS frameworks, and external services parsed from HTML.
- Offers JSON output and scripting-friendly subcommands for WHOIS, DNS, mail, TLS, HTTP, SEO, stack detection, and full reports.
Website: github.com/retlehs/quien
Support:
Developer: retlehs
License: MIT License

quien is written in Go. Learn Go with our recommended free books and free tutorials.
Related Software
| Alternatives to whois | |
|---|---|
| GNOME Nettool | Performs ping, netstat, traceroute, port scans, lookup, and whois (GUI) |
| jwhois | Improved whois client |
| ipwhois | Retrieve and parse whois data for IPv4 and IPv6 addresses |
| OpenRDAP | Command line RDAP client implementation in Go |
| rdapper | Simple console-based RDAP client |
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