The Kelly Criterion betting calculator should be used to determine the optimal stake size for your bets. No matter how great a bet looks, your stake needs to be appropriate relative to how much value you’re actually achieving with your bet. This is a large differentiating factor between those who treat betting as a calculated game of numbers and those who gamble on gut feelings and emotion. 

To use the calculator, first set your Kelly multiplier. If you don’t know what this is, leave it at “1”. Next enter the odds you’re betting with on your bookie. Then enter the true probability of that bet winning in percentage format – an example would be if you’re betting “heads” on a coinflip, type 50%. Lastly enter your bankroll. The calculator will use this figure to determine what your stake will be as a dollar amount.