The calculator I use is this one. http://completecurrencytrader.com/streak-probability-calculator.php

To get anything meaningful there is no point just looking at the probability of 14 out of 14 bets having a particular result as in reality nobody only ever makes 14 bets. You also need to consider the sample size, total number of bets, to find out how likely something is to occur. I usually look at 10,000 as the sample to give a reasonable comparison. In this case, the result is a 43.7% chance of hitting a 14 streak.