Online shoppers usually look for their desired products with maximum discount possible, as larger discounts tend to influence the consumer behavior. However, the price of a product also plays significant role in buying decision because of the limited budget. In this paper, to optimize the shopping decision, a 0/1 knapsack problem is formulated, and a comparison of the traditional recursive solution method and the dynamic programming optimization approach is made. The results show that the dynamic programming method outperforms the recursive solution method in terms of computational time for large number of purchase items.