Console Calculator may be downloaded and evaluated for free, however a license should be purchased for continued use.  There are no enforced restrictions for unlicensed use, but it’s just $5 USD. I’ve kept the price very low, so there is no excuse to not register.

Licenses are per-user, rather than per-machine, so you can use CCalc on as many computers as you wish with your license.  All updates are always free.