Just tried to do a whois check at whois.sc (now domaintools ... stupid name, fantastic looking site) and it requires registration. I hate sites that require registration ... I guess I'll be taking my whois searches elsewhere.
Yes, that's true. They have ever only allowed 5 searches today without registration. Signup is very easy at Domaintools, just enter your email, click the link, and enter your password. You also get lots of other features including whois history checks.asianinvasion said:They have required forced registration for as long as I can remember.
They allow you to do a certain amount of WHOIS queries per day.
If you exceed the quota, then they force you to register.
This is to prevent automated WHOIS queries.

