freeformatter.comは安全ですか？

Most of this site's content is very useful, as it deals with web script and data validation. However, one of the sections deals with Credit Card number validation and generation! While it gives instructions on how to do the validation yourself, it ALSO has an input box where you can enter YOUR CREDIT CARD NUMBER for validation!!! Furthermore, the page lists three dozen FAKE credit card number, three for each and every credit card used around the world. And if those aren't enough for you, you can press the Reset button to have it generate three dozen more FAKE numbers! As I said, the rest of the information on this site is extremely useful, but the credit card section, while it very well may be intended simply for instructional purposes, strains the boundaries of ethical web content!!!