As others have said, DNS is distributed/hierarchical/delegated. But if you wanted to try... First, grab the root zone file which points to all the TLD nameserv

As others have said, DNS is distributed/hierarchical/delegated. But if you wanted to try... First, grab the root zone file which points to all the TLD nameservers: https://www.internic.net/domain/root.zone https://www.internic.net/domain/root.zone Next, get zone files for the TLDs themselves. Not every TLD makes that freely or easily available, but https://github.com/jschauma/tld-zoneinfo https://github.com/jschauma/tld-zoneinfo is an excellent resource. The author of the above repo runs https://netmeister.org/tldstats/ https://netmeister.org/tldstats/ which will give you an idea of scale; they're able to get 98.89% of all TLDs. (Correction: zone files for ccTLDs are mostly unavailable. That 98.89% is only domain count coverage, not zone file coverage.)