The porosity of fibers electrospun from polystyrene (PS)/dimethylformamide (DMF) solution at environmental conditions of 40 degrees C and 60% relative humidity is characterized by three principally different methods, i.e. thermoporometry, nitrogen adsorption/desorption (according to BET, DFT and BJH theories) and density measurements. Different aspects of porosity including mean pore radius, specific surface area and total pore volume of electrospun fibers are evaluated. Results demonstrate that each of these aspects can be best described by one of the investigated techniques. In other words the mentioned methods act as complementary approaches to make known the characteristic of porous electrospun fibers. (C) 2012 Elsevier B.V. All rights reserved.