I also have a version of the calculator I use that is linked to live data feeds from ThinkorSwim (ToS). It updates the SPX and VIX in real time along with premiums for the suggested spreads. It then calculates the potential max return for each trade along with the probability of success for that spread being pierced both intra-period and at the expiration date.

Here is an example of how this spreadsheet looks.

https://www.dropbox.com/s/pnjvr3xxsi...31.36.png?dl=0

Note: I am not distributing this automated spreadsheet linked to ToS at this time as I have not found a way to protect it in order to keep my proprietary formulas from being copied / shared.

I do use this when discussing with members on the chat-room and post live screen shots of it for members to use in their evaluating spreads.