An enhanced scalable compact model for on-chip RF CMOS spiral inductors is presented. By considering layout and technology parameters, under quasi-static approximation, the model elements are all expressed analytically and based on electromagnetic effects. Frequency dependent behavior of CMOS spiral such as skin and proximity effects, and decrease of equivalent series resistance due to substrate coupling is considered. The model is suitable to be easily implemented in design kits by foundry and provides interesting accuracy to be used by CMOS Radio Frequency Integrated Circuits designers. (C) 2011 Elsevier Ltd. All rights reserved.