The Darth Vader theme song should be played when most investors look at the fees they are paying.

FeeX offers one of the easiest ways to learn just how much you're paying in fees and then do something about it. The site is free to use.

You simply sign up and link your retirement and trading accounts. FeeX uses a very sophisticated database to show you the fees on your portfolio and tell you if those fees are low, medium, high or sky high.

If you aren't in the low bucket (and even if you are), FeeX will recommend ways to reduce your fees. Another incredibly helpful function is FeeX can tell you if you should rollover an old 401(k) plan from a prior job to an IRA. This can save you a lot of money if it's done right.

"Typically, people tend to reduce their fees by about 85%," says Yoav Zurel, co-founder and CEO of FeeX. He's a mathematician who founded FeeX with friends because he was stunned at how hard it was, even for him, to figure out the fees on his investments.

So far, FeeX has analyzed "tens of thousands" of people's accounts. It even won the "Most Disruptive" company prize at the 2016 Benzinga Fintech Awards.