Everything this tool does, and why it's built that way.
Every lookup resolves IPv4 and IPv6 records independently through Node.js's built-in dns module.
Paste thousands of domains at once. Large batches run as background jobs, not blocking requests.
A configurable worker pool resolves domains in parallel without ever flooding DNS with an unbounded burst of queries.
Transient failures (timeouts, SERVFAIL, REFUSED) are retried with exponential backoff. Permanent failures like NXDOMAIN fail immediately -- no wasted retries.
Every resolved address -- not just the requested hostname -- is checked against private, loopback, link-local, and cloud-metadata ranges, closing the DNS-rebinding gap most tools miss.
Download full job results without waiting on a giant in-memory export -- results stream to your browser as they're read from the database.
The same job pipeline that powers bulk lookups supports one-time and recurring schedules under the hood, persisted so they survive a restart.
Point resolution at any DNS servers you trust (Cloudflare and Google by default) via environment configuration -- nothing hard-coded.
Results describe what the configured DNS resolver publicly returned at lookup time. They do not claim to identify an origin server behind a CDN, reverse proxy, or load balancer. See the resolution methodology and security details for the boundaries of the service.