I am happy to report that our StraddlesCalc V2 tool is online. You can use it here.
The tool is a great way to see what are the maximum moves required for straddles and strangles, as well as to determine optimal position sizing for a given amount of invested dollars.
Examples from late today:
For UCO, September:
The above shows that the maximum move required is 19.77%, and that you should buy 13 calls and 11 puts for the $2k investment. This is the maximum move required for profitability. In general, the move will be smaller if the straddle is sold early.
For UNG, September:
For GAS.to, December:
This confirms that gas.to requires much lower premiums (liquidity is very low however), as posted earlier.