pkaESSRIM.py is a program to find out the energy spectra of recoil atoms from the results of simulations using SRIM-2013 in a user-defined energy bin structure and also plot the spectra. It will be useful to characterize ion-irradiation environments and corresponding related works. These points refer to the program pkaESSRIM.py:- --> pkaESSRIM.py is an interactive program to produce energy spectrum of recoil (pka) atoms formed due to impact of energetic ions. --> first do an ion simulation for large number of times in SRIM-2013 with 'Quick' calculation mode and write the output in its collision.txt file. --> keep this collision.txt file in your working directory. --> prepare your recoil energy bins in a file called RecoilEnergyBins with number of energy points in the first line and a comment in the second line (see the file in the distribution). --> run the program by giving inputs interactively. --> get the output data files and the plots. Please cite the following reference while using the program: [Reference: A Study of Neutron and Ion Irradiation Induced Atomic Recoil Spectra with Newly Developed Tools RMINDD and pkaESSRIM for Materials Modelling website: https://events.tuni.fi/uploads/2023/03/f1611564-pysicsdays2023_talk_abstracts.pdf (page 21)] Thank you for using the program pkaESSRIM.py.