This document describes a procedure for the determination of elastic modulus for compliant materials using atomic force microscope (AFM). Force-distance curves on the surface of compliant materials are measured and the analysis uses a two-point method based on Johnson-Kendall-Roberts (JKR) theory. This document is applicable to compliant materials with elastic moduli ranging from 100 kPa to 1 GPa. The spatial resolution is dependent on the contact radius between the AFM probe and the surface and is typically approximately10-20 nm.