Modern Loan Calculator App using Python Tkinter

By Kaushik karthikeyan K

This Project is to develop a Loan Calculator app using Tkinter(GUI application) in Python Language. This application will calculate the Total loan amount for you.

Introduction to Tkinter Module:

Python offers many options for Graphical User Interface. Tkinter is the most popular one Since Python with Tkinter outputs the easiest and efficient way to create GUI applications.

 

Requirements:

Python Any Versions

Tkinter Module

 

Coding:

from tkinter import *           

class LoanCalculator:
    def __init__(self):   
        window = Tk() 
        window.title("Modern Loan Calculator") 
        window.configure(background = "gold")  

       
        Label(window, font='Helvetica 12 bold',text="Annual Interest Rate").grid(row=1,column=1, sticky=W)
        Label(window, font='Helvetica 12 bold',text="Number of Years").grid(row=2,column=1, sticky=W)
        Label(window, font='Helvetica 12 bold',text="Loan Amount").grid(row=3,column=1, sticky=W)
        Label(window, font='Helvetica 12 bold', text="Monthly Payment").grid(row=4,column=1, sticky=W)
        Label(window, font='Helvetica 12 bold',text="Total Payment").grid(row=5,column=1, sticky=W)


        self.annualInterestRateVar = StringVar()
        Entry(window, textvariable=self.annualInterestRateVar,justify=RIGHT).grid(row=1, column=2)

        self.numberofYearsVar = StringVar()
        Entry(window, textvariable=self.numberofYearsVar,justify=RIGHT).grid(row=2, column=2)

        self.loanAmountVar = StringVar()
        Entry(window, textvariable=self.loanAmountVar,justify=RIGHT).grid(row=3, column=2)

        self.monthlyPaymentVar = StringVar()
        lblMonthlyPayment= Label(window,font='Helvetica 12 bold',bg ="light green", textvariable=self.monthlyPaymentVar).grid(row=4,column=2, sticky=E)

        self.totalPaymentVar = StringVar()
        lblTotalPayment= Label(window,font='Helvetica 12 bold',bg ="light green", textvariable=self.totalPaymentVar).grid(row=5,column=2, sticky=E)


        btComputePayment = Button(window, text="Compute Payment",bg="red",fg="white",font='Helvetica 14 bold', command=self.computePayment).grid(row=6, column=2, sticky=E)
        btClear = Button(window, text="Clear",bg="blue",fg="white",font='Helvetica 14 bold', command=self.delete_all).grid(row=6, column=8, padx=20,pady=20 ,sticky=E)

        window.mainloop()  


    def computePayment(self):
        monthlyPayment = self.getMonthlyPayment(
            float(self.loanAmountVar.get()),
            float(self.annualInterestRateVar.get())  / 1200 ,
            int(self.numberofYearsVar.get()))


        self.monthlyPaymentVar.set(format(monthlyPayment, '10.2f'))
        totalPayment = float(self.monthlyPaymentVar.get()) * 12 \
         * int(self.numberofYearsVar.get())

        self.totalPaymentVar.set(format(totalPayment, '10.2f'))


    def getMonthlyPayment(self,loanAmount,monthlyInterestRate,numberofYears):
        monthlyPayment = loanAmount * monthlyInterestRate / (1-1/(1 + monthlyInterestRate)** (numberofYears * 12 ))
        return monthlyPayment   


    def delete_all(self) :
        self.monthlyPaymentVar.set("")
        self.loanAmountVar.set("")
        self.annualInterestRateVar.set("")
        self.numberofYearsVar.set("")
        self.totalPaymentVar.set("")





LoanCalculator()

 

Output:

 

Conclusion:

     From the Above project, we learnt some modules in Tkinter and how to calculate Loan amount and combine these two we create an application.