A fast tool for performing horizontal domain enumeration.

Installation • Usage • Running Seekly

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Seekly is a horizontal enumeration tool. This means the tool searches for domains related to an initial domain by leveraging WhoisXMLAPI's APIs.

Installation Instructions

Seekly requires go 1.24.1 to install successfully.

go install github.com/LucasKatashi/seekly/cmd/seekly@latest

Usage

seekly -h

This will display help for the tool. Here are all the switches it supports.

Usage:
 ./seekly [flags]

INPUT:
 --domain		enter the target domain
 --wildcard		performs a wildcard search to return all domains containing the value specified with --domain.
            for instance, using `--domain example.com` will match domains like *example*.com
 --api-key		enter your WhoisXMLAPI API key

OUTPUT:
 --output		generates an output file containing the discovered domains
 --silent		ignore the banner when running the tool

Running Seekly

Seekly requires a WhoisXMLAPI API key to run. You can get your key here.

You can provide the key either by using the --api-key/-api-key flag or by setting it as an environment variable in your current session:

export WhoisXMLAPIKey="API_KEY"

Running Seekly without the --wildcard flag ensures you're only retrieving domains that are actually related to the one specified with --domain. By default, Seekly performs recursive lookups using WHOIS-related fields like email, person, owner, etc., to discover associated domains.

When using the --wildcard flag, Seekly instead performs a wildcard-based search for any domain containing the given domain value, restricted to the same TLD. For example:

--domain example.com --wildcard

Will result in a query like:

*example*.com

Seekly also integrates seamlessly in toolchains to further refine your recon. For example:

seekly -domain example.com -silent | subfinder -all -silent | httpx -fr -mc 200 -t 150 -silent | katana -jc -jsl -d 4 -c 20 -silent --output example.txt

⚠️ Keep in mind that Seekly can significantly consume your WhoisXMLAPI credits, as it performs recursive lookups using WHOIS queries, Reverse WHOIS, the Domains & Subdomains API, and more.