Python – Compound Interest GUI Calculator using Tkinter

Last Updated : 08 Dec, 2022

Prerequisites : Introduction to tkinter | Program to calculate compound interest

Python offers multiple options for developing a GUI (Graphical User Interface). Out of all the GUI methods, Tkinter is the most commonly used method. In this article, we will learn how to create a Compound Interest GUI Calculator application using Tkinter, with a step-by-step guide.

To create a Tkinter:

Importing the module – tkinter
Create the main window (container)
Add any number of widgets to the main window.
Apply the event Trigger on the widgets.

Below is what the GUI will look like:

Let’s create a GUI based Compound Interest Calculator application.

Below is the implementation :

Python3

# import all classes / functions from the tkinter
from tkinter import *
 
# Function for clearing the  
# contents of all entry boxes   
def clear_all() :
 
    # whole content of entry boxes is deleted 
    principal_field.delete(0, END)   
    rate_field.delete(0, END) 
    time_field.delete(0, END)
    compound_field.delete(0, END)
   
    # set focus on the principal_field entry box  
    principal_field.focus_set() 
 
 
# Function to find compound interest  
def calculate_ci(): 
 
    # get a content from entry box
    principal = int(principal_field.get())
     
    rate = float(rate_field.get())
 
    time = int(time_field.get())
     
    # Calculates compound interest  
    CI = principal * (pow((1 + rate / 100), time))
 
    # insert method inserting the  
    # value in the text entry box.
    compound_field.insert(10, CI)
 
     
 
# Driver code 
if __name__ == "__main__" : 
   
    # Create a GUI window 
    root = Tk() 
   
    # Set the background colour of GUI window 
    root.configure(background = 'light green') 
   
    # Set the configuration of GUI window 
    root.geometry("400x250") 
   
    # set the name of tkinter GUI window 
    root.title("Compound Interest Calculator")  
       
    # Create a Principal Amount : label 
    label1 = Label(root, text = "Principal Amount(Rs) : ", 
                   fg = 'black', bg = 'red') 
   
    # Create a Rate : label 
    label2 = Label(root, text = "Rate(%) : ", 
                   fg = 'black', bg = 'red') 
       
    # Create a Time : label 
    label3 = Label(root, text = "Time(years) : ", 
                   fg = 'black', bg = 'red')
 
    # Create a Compound Interest : label 
    label4 = Label(root, text = "Compound Interest : ", 
                   fg = 'black', bg = 'red') 
 
    # grid method is used for placing  
    # the widgets at respective positions  
    # in table like structure .
 
    # padx keyword argument used to set padding along x-axis .
    # pady keyword argument used to set padding along y-axis . 
    label1.grid(row = 1, column = 0, padx = 10, pady = 10)  
    label2.grid(row = 2, column = 0, padx = 10, pady = 10)  
    label3.grid(row = 3, column = 0, padx = 10, pady = 10)
    label4.grid(row = 5, column = 0, padx = 10, pady = 10)
 
    # Create a entry box  
    # for filling or typing the information.
    principal_field = Entry(root)  
    rate_field = Entry(root)  
    time_field = Entry(root)
    compound_field = Entry(root)
 
    # grid method is used for placing  
    # the widgets at respective positions  
    # in table like structure .
     
    # padx keyword argument used to set padding along x-axis .
    # pady keyword argument used to set padding along y-axis . 
    principal_field.grid(row = 1, column = 1, padx = 10, pady = 10)  
    rate_field.grid(row = 2, column = 1, padx = 10, pady = 10)  
    time_field.grid(row = 3, column = 1, padx = 10, pady = 10)
    compound_field.grid(row = 5, column = 1, padx = 10, pady = 10)
 
    # Create a Submit Button and attached  
    # to calculate_ci function  
    button1 = Button(root, text = "Submit", bg = "red",  
                     fg = "black", command = calculate_ci) 
   
    # Create a Clear Button and attached  
    # to clear_all function  
    button2 = Button(root, text = "Clear", bg = "red",  
                     fg = "black", command = clear_all)
   
    button1.grid(row = 4, column = 1, pady = 10) 
    button2.grid(row = 6, column = 1, pady = 10)
 
    # Start the GUI  
    root.mainloop()
    