First, I would like to clarify that this review is not of the content or service that DomainTools provides, but rather a review of their business practices.
I have enjoyed some of the limited free services that they provide. They provide free Whois, DNS, and a few other lookup tools. The types of lookups that use their database rather than just making an on-the-spot query cost money as expected.
A few days ago I did a Whois lookup and wanted to see what other domains were registered in that person’s name. This is a paid report of an estimated $100. I saw the link for a free trial of the paid account. I signed up because they are a popular website and I expected I could delete my account when I was done. As you may expect they require payment information so after the free trial they can bill me. I entered a credit card expecting I could delete it later.