Nanoindentation is a widely used technique to measure the mechanical properties of films with thickness ranging from nanometers to micrometers. A much better understanding of the contact mechanics is obtained mostly through finite element modeling. The experiments were modeled using the software package Nano SP1 that is based on COSMOSM™ (Structural Research & Analysis Corp, www.cosmosm.com), a finite element code. The fundamental material properties affecting pile-up are the ratio of the effective modulus to yield stress Eeff/σ and the work hardening behavior. Two separate cases of work hardening rates were considered; one with no work hardening rate and other with a linear work hardening rate. Specifically, it is observed that pile up is large only when hf/hmax is close to one and degree of work hardening rate is small. It should also be noted that when hf/hmax < 0.7 very little pile-up is observed no matter what the work-hardening behavior of the material. When pile-up occurs the contact area is greater than that predicted by the experimental methods and both the hardness and modulus are overestimated. In this report the amount by which these properties are overestimated are studied and got to be around 22% approx. Bluntness of the tip …