Show HN: Ldns.com – fast DNS lookups from the URL bar

4 jmorf 1 8/15/2025, 4:46:57 PM ldns.com ↗

I built LDNS because I'm constantly curious about domain names - who owns them, which nameservers they use, how they're configured, and what their DNS records reveal. I wanted a fast, easy way to investigate domains right from my browser without juggling multiple tools.

LDNS runs entirely client-side using Cloudflare's DNS over HTTPS. Just type a domain and instantly see:

All DNS records with clickable filtering RDAP/WHOIS data with registrar info and expiration dates Email security configuration (SPF, DMARC, MTA-STS, BIMI) Export options (JSON, CSV, BIND zones, PDF reports)

Try it at ldns.com - just append any domain like ldns.com/example.com to start investigating.

Built with SvelteKit and deployed on Cloudflare Pages for that instant-load experience we all love.

Comments, feedback, and feature requests welcome!

Comments (1)

slig · 1h ago

I liked it, specially that it's blazing fast. I too used the RDAP API in a side project recently and it was so damn easy. Thanks for sharing.

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Show HN: Ldns.com – fast DNS lookups from the URL bar

Comments (1)