Energy loss and straggling in Ag and Sn metallic foils for a-particles, using 241 Am source, are measured. The measured energy loss values are compared with the predicted values based on Benton and Henke, Grande and Schiwietz (CasP), Ziegler et al. (SRIM) formulations and ICRU-49 report (ASTAR). Also, measured straggling values of a-particles are compared with the computed values adopting practically used four collisional (Bohr, Lindhard and Scharff, BetheeLivingston, Titeica) formulations and one collisional plus charge exchange (Yang et al.) straggling formulation. The aim of the comparison is to identify the best energy loss and straggling formulation.