Estimating permeability is very important for accurate reservoir characterization. A lot of money and effort is invested in determining the permeability accurately. In this study we propose two novel approaches in estimating permeability from well logs. The first approach involves the usage of a fractal based approach and using Monte-Carlo simulation in estimating permeability from density and gamma ray logs. The second approach estimates permeability using a modified Kozeny-Carman model by using porosity information. Both the methods have been tested on a sandstone reservoirs in the F3 Block of the Dutch sector in the North Sea. Both the methods successfully estimated the permeability and a comparision of results are made. The utilities of both the approaches are discussed and it is concluded that for accurate results a balanced approach is needed.