Domain Hunter checks hundreds of domains at once and exports the results to CSV.
Free, open-source bulk domain checker.

Why I built it
Checking domain availability across multiple TLDs used to be painfully slow. Web-based WHOIS tools make you search one by one, throw ads at you, or hit you with rate limits and CAPTCHAs. I wanted a fast, local tool that could bulk-check domain availability straight from my desktop, without any of that overhead.

How I solved it

• Queried domains directly via RDAP (Registration Data Access Protocol) instead of raw WHOIS, for accurate, standardized registry checks
• Built an adaptive throttling engine that adjusts query delay in real time to stay under registry rate limits, avoiding IP blocks while running at ~1 domain/sec
• Added a TLD builder that automatically appends selected extensions (.com, .net, .org, custom keywords) to base terms
• Used SQLite for local queue tracking and state management, with full CSV export via CsvHelper
• Persisted the entire query queue to disk — close the app mid-scan, and it picks up exactly where it left off with a single “Resume” click; results stay saved until you clear them

Result
Domain Hunter bulk-checks hundreds of domains without browser overhead or manual rate-limit juggling, survives restarts without losing progress, and exports clean, ready-to-use CSV datasets in seconds.