Understanding the physics behind the contact resistance at metal-CNT interfaces is of crucial importance for the development of high-performance CNTFETs. Using parameter-free model, we show how the contact resistance and on-current of a carbon nanotube FET depend on the quality of the metal/CNT contact for a variety of three metals representing week, medium and week metal-CNT interaction strength. (A. Fediai et al. in Applied Physics Letters, doi: 10.1063/1.4962439)