Clandestine Development Guides and utilities for sysadmins

Batch DNS Lookup

Batch DNS Lookup enables you to do multiple DNS lookups fast and in a very simple manner. The core part of the application is built using the free .NET DNS Client Library from JH Software (


You paste in a bulk list of domain names in the box on the left side. Then you choose wich settings to use and start the DNS lookup process. You can choose which type of records to lookup. If you do a lookup for an A-record for a domain that initially points to a CNAME record, then the application will continue to lookup those records, until it gets the underlying A-record.


Only log the last record looked up: I often use this option for nameservers and MX records. It only returns one record (the last one looked up), no matter how many records there might be for a particular domain record. It also only returns the A-record in a recursive lookup.

Enable custom DNS servers: Allows you to specify which servers to use for DNS lookups. If this option is not enabled, the application will use the default DNS servers specified on your system.

Enable multithreaded queries: Enabled per default. Will do multiple lookups at the same time, speeding up the time it takes to complete your list of domains.

Enable debug logging: Gives detailed information on the whole lookup process.


Changes in v1.2.2.0

  • Fixed bug with reverse lookups.
  • Added support for IPv6 lookup using AAAA and PTR records


Changes in v1.2.1.0

  • Added custom delimiter option in export dialog.
  • Added option to export to clipboard.
  • Added setting to define query timeout and retries.
  • Added more details to the debug logging.


Changes in v1.2.0.0

  • Switched to JH Software's DNS Client Library for more stability and options.
  • Added multithreaded lookup option. Measured a speed increase of up to 80% compared to single threaded lookups.
  • Added option to export results to CSV.
  • Simplyfied the UI, moved most of the settings to it's own window. Settings are saved per user basis.
  • Added an option to specify custom DNS servers.
  • Added option to enable debug logging for more information.
  • Fixed bug that didn't allow CTRL+A shortcut in the two textboxes.
  • Added IDN support.
  • Added ability to lookup more record types.



Download Batch DNS Lookup (191kb, requires .NET 2.0)