Whois.re is intended to lookup almost all Whois domain, Whois IP, Whois ASN, check domain availability, geo IP Location, PR(Google Page rank) & Alexa rank. You can see registrant data for Domain, IP(Internet Protocol) address and ASN(Autonomous System Number). Currently, Whois.re supports to lookup top-level domains(TLDs), country code top-level domains (ccTLD), generic top-level domains (gTLD), second-level domain (SLD), internationalized domain name (IDN), Internet Protocol (IP) address and Autonomous System Number (ASN).
Bulk WHOIS Lookup Tool Software
To easy access whois.re from your computer use this small software. It's free from Virus/malware, you can check in virustotal.com
After installed, this software will run in systray windows. You can check whois data in bulk.