Subdomain Discovery guide
Find every subdomain of any domain via public certificate transparency logs (crt.sh). 100% live, no API key. Reveals what attackers can already see — sales, staging, internal admin panels, forgotten infrastructure.
How to use it
Three steps to a result
Open the tool
Sign in free and open Subdomain Discovery.
Fill in the inputs
Root domain.
Review and use the output
Copy, export or save the result, and check the data label to see how it was produced.
Details
What to expect
Live dataWhere the data comes from
Fetched in real time from an authoritative API (Google, DataForSEO, etc.). The numbers are real.
Free tierUnlimited
This tool runs on free APIs (Google / open data): unlimited usage on every plan.
What you need to provide
- Root domainExample: example.com
Ready to try Subdomain Discovery?
Free to start. No credit card.