Abstract: The invention relates to a computer implemented method and system for determining homoeopathic medicinal potency to patient based on Nigam's Potency scale. The said method to determine the homoeopathic medicinal potency based on Nigam's potency scale which is stored in a memory unit which is being retrieved based on the input given to the system through an input device. All instruction are carried out by the processing element. Nigam's potency scale works-in a new way to determine potency. The system takes in a set of numbers depending on the tabs a user clicks, adds them up and displays the result according to the range in which the number falls. The scores range from 18(lowest) to 54(highest). The division of scores and result is done as follows: 1) 18-30: Use low potency (1X/D1 to 6X/D6/3C) 2) 31-42: Use medium potency (4C TO 12C) 3) 43-46: Use high potency (30C) 4) 47-50: Use very high potency (200C) 5) 51-54: Use ultra-high potency (1M, 10M, 50M, 100M/CM; 1M=1000).