I'm trading the Bearish Butterfly (and occasionally the M3). Usually I calculated the mid price for the Butterfly combination by hand (from the mid price of the 3 strike prices). But in one of his weekly videos John Locke talked about not only doing this for the Put Butterfly, but also for the Call and Iron Butterfly. This was too much "by hand" and I started writing a small tool that connects to IB TWS API and does the calculation. Today I released the first version. It is free to use and you may download it at http://www.BBpricer.com/. It is a console program and I think especially for Windows users this is a little bit rough. I assume with a batch file one could also start it via desktop. But I'm not much of a Windows user. So I welcome any suggestions to make usage easier. Also, if you find any bugs, please reply here or email me (see web page). PS: Tom, if this announcement is not okay (I'm mentioning an URL) - please feel free to delete this post or the link. Update: I also trade broken-wing butterflies and BBpricer's interface was not flexible enough to handle them. Over the last months I have written a new software, which is more flexible: https://www.option-poption.com/.