Hey..Just check out this online FREE calculator created by us..
http://am22tech.com/s/22/Tools/InHandSalaryIndia.aspx
Teh calculator asks you to input the break up of your salary like basic sal, HRA etc and then computes your yearly tax and shows you the amount that you will get as take home.
Also, the calculator analyzes your salary structure and investment details and suggests you various ways on how you can save tax and increase your take home pay.
I hope it will help you.