Vester Tester is a calculator designed for use by execs contemplating changing employers. It lets them compare current compensation with that offered by a potential employer.
Researchers can use it to calculate or project compensation for public company insiders.
You can use it for private company prospects too, but there's a lot more guesstimating involved. Before using Vester, note the fields you have to fill in on each page of the calculator. This will help because, gasp, you have to do some research before you use it. Gathering as much concrete information as you can beforehand really helps get your calculations as close as possible to the real thing. Then you will need to check out the current stock price.