Download Free Nutritional Calculator in Python Using Tkinter GUI with Source code. Python Projects with Source code. Nutritional Calculator is a simple project developed in Python. Nutritional Calculator contains a Python Script (gui.py). Nutritional Calculator is a simple GUI based Desktop Application in Tkinter which is user Friendly and very easy to understand. This Application deals with the health related activities. This basically calculate the intake the calories in Food. This Project is very useful for educational purpose.