dnsx
dnsx is a fast DNS toolkit for running many queries and resolving large lists of hostnames.
Legal & ethical use. Use this tool only on systems, networks and data that you own or have explicit written permission to test. Unauthorised access or scanning can break computer-misuse laws (for example Pakistan's Prevention of Electronic Crimes Act, 2016, and equivalents elsewhere). Practise in your own lab or in authorised environments such as CTFs.
What it is used for
- Resolve a list of subdomains to see which exist
- Query specific record types at scale
Key features
- Multiple record types
- Wildcard filtering
- Pipeline friendly
Installation
Install a release binary or via Go.
Beginner usage guide
Combine with Subfinder: pipe discovered names into dnsx to keep only those that resolve.
Example commands
Run these only against your own lab or authorised targets. Placeholder addresses such as 192.0.2.x are documentation ranges.
Resolve a list of hostnames
dnsx -l subdomains.txt -a -resp-l reads names from a file, -a requests A records and -resp prints the answers.
References
Source verification
Last reviewed: 2026-10-27
Links checked over HTTP: 2026-10-27 07:51 UTC — official: 200, docs: 200, repo: 200
Commands were written from the official documentation and have not been executed on this site; test them in your lab.