Finding and Identifying sub-domains

Job ID: 31600873

Budget: $30 – $250 USD

We are looking a one time service from a freelancer, who could help us to identify all existing subdomains from a url. We have found out the sub-domains through the tools that available already.

So, if we would chose a domain, e.g. example.com, we would like to identify all existing subdomains, like 123.example.com, 456.example.com, 789.example.com ...

Is this possible anyone could you offer us a solution?

PS: Before you bid for the project, there might be a quick screening task which will take probably 30 mins. The task will be as easy as just letting me know how many sub-domains are there for a specific domain that I share with you.