Domain Name Research
Quickly check availability of multiple domain name candidates when brainstorming names for your new project, business, or website. Save time by checking dozens of domains at once.
Domain Availability Checker
Batch check domain registration status using DNS or WHOIS lookup.
Check Results
Run domain check to see results
Overview
Domain Availability Checker is a powerful tool for batch checking whether domain names are registered or available. It supports two checking methods: Fast Mode using DNS-over-HTTPS for quick checks, and Detailed Mode using WHOIS API for comprehensive registration information including registrar details and expiry dates.
Use Cases
Domain Portfolio Management
Monitor the registration status of domains in your watchlist. Check if expired domains have become available or verify the status of domains you're interested in acquiring.
Competitor Analysis
Research domain portfolios of competitors or check if related domain variations are registered. Useful for brand protection and market research.
Bulk Domain Validation
Validate large lists of domains for marketing campaigns, SEO research, or data cleanup. Identify which domains in your database are still active.
How to Use
Choose Check Method
Select Fast Mode (DNS) for quick checks of many domains - it uses DNS-over-HTTPS to detect if domains have DNS records. Choose Detailed Mode (WHOIS) for accurate registration information including registrar, creation date, and expiry date.
Enter Domain Names
Paste your domain list with one domain per line, or separate them with commas or semicolons. The tool will automatically parse and clean the input. You can include or exclude the "www." prefix - it will be handled correctly.
Review Results
Results show each domain's status (Available, Registered, or Error), the check method used, and additional details. For WHOIS checks, you'll see registrar information and important dates when available.
Frequently Asked Questions
What's the difference between Fast Mode and Detailed Mode?
Fast Mode (DNS) checks if a domain has DNS records configured, which usually indicates registration. It's very fast but may occasionally show false positives for registered domains without DNS. Detailed Mode (WHOIS) queries the domain registry directly for accurate registration information, but it's slower and may have rate limits.
Why does Fast Mode show a domain as available when it's actually registered?
Fast Mode checks for DNS records, not registration status. A registered domain without configured DNS records will appear as available. For accurate results, use Detailed Mode (WHOIS) which checks the actual domain registry.
How many domains can I check at once?
You can check multiple domains in one batch. However, to avoid rate limiting, there's a small delay between checks (200ms for DNS, 1000ms for WHOIS). Checking many domains with WHOIS may take several minutes.
Does this tool support all domain extensions?
The tool supports most common domain extensions (.com, .net, .org, country codes, etc.). However, some newer or specialized TLDs may have limited WHOIS data availability. DNS checking works for all domains with standard DNS configuration.
Is my domain search private?
DNS checks are made through Cloudflare's public DNS-over-HTTPS service. WHOIS checks use a third-party API. While these services may log queries, the tool itself doesn't store your searches. For sensitive domain research, consider using a VPN.
Related Tools
Concept Notes
Domain lifecycle realities
WHOIS and DNS data propagate with lag, so availability checks can differ across registrars and resolvers. Before go-live, align A/AAAA, CNAME, and TXT (SPF/DKIM) records and set sane TTLs—stray legacy records or mismatched caching often cause intermittent resolution or mail deliverability issues.