When playing the game of Catan, understanding the probabilities and real cost of development card is a difficult task.
In Development Card cost calculator you set you card drawing targets, and simulate card drawing to see in real time how probabilities evolve and how much card you can be expected to buy before reaching your goal. You will also view the real cost of buying cards, which takes into account the return of all types of cards you can be expected to draw along the way.
Note: This is not a replacement for any part of the Catan Game. Only a useful tool to understand cards probabilities and simulate the outcome of drawing cards in the game.