I couldn't really find anything so I decided to write my own.  

Calculating the retrace values is simple.  For example, if the high price is 119.00 and the low price 104.20 and you want the 23.6% retrace value, the formula is:

(high price - ( (high price - low price) x .236 ) )  or

(119.00 - ( (119.00 - 114.20) x .236 ) ) =  117.8672

You can get to the calculator from the home page right menu or go to forex fibonacci calculator.