This study is prepared to produce solutions for estimating vehicle traffic density which is one of the biggest problems of urban life today. Four different algorithms are proposed for density estimation problem with different perspectives. All these proposed algorithms have been tried to estimate next state of the road by looking at history of density data. Algorithms are inspired by the methods used to estimate spectrum holes in cognitive radio channels. A similar approach is used for estimation of traffic density. In this study, Istanbul Metropolitan Municipality Traffic Control Center data received from the busiest roads of Istanbul in 2013, have been used as traffic data. Different simulations have been performed using these algorithms and results are evaluated based on several performance criteria.