Network toolkit

Modern WHOIS & DNS intelligence

Fast, mobile-ready tools for WHOIS, DNS, IP, and device insight — all in one place.

Subdomain Finder (passive)

Subdomain Finder Overview

The StripDNS Subdomain Finder tool is built for fast, practical checks when you need reliable answers without jumping between multiple dashboards. Discover known subdomains using passive techniques. It is especially useful for asset discovery and exposure review, whether you are diagnosing outages, validating infrastructure changes, or preparing before a migration. Results are optimized for speed and readability so you can move from detection to action quickly during production incidents. For best outcomes, compare findings over time, cross-check with related DNS and TLS tools, and rerun checks after each config update to confirm changes propagated as expected.

How To Use This Tool

Common Use Cases

  • Discover known public subdomain footprint.
  • Support inventory and exposure review.
  • Assist incident scoping for affected assets.

Recommended Steps

  1. Enter a valid domain, hostname, or IP based on the tool input format.
  2. Run the lookup and review key output fields first before deep details.
  3. Repeat after any DNS, network, or infrastructure change to confirm results.

Interpretation Tips

  • Compare results over time instead of relying on a single snapshot.
  • Cross-check with related tools for stronger confidence.
  • Document findings with timestamps during incident handling.
FAQ

This uses passive sources and known datasets, not guaranteed exhaustive brute force.

Private or newly created hosts may not appear in passive indexes yet.

Yes. Historical records can remain visible after decommissioning.

Validate each host; some entries may be stale or not publicly reachable.