Welcome folks today in this blog post we will be building a basic calculator which performs four operations such as addition and subtraction and division and multiplication. All the source code of the application is given below.

Get Started

In order to get started we need to install python inside our system. And now we also need to install tkinter module using the pip command

pip install tkinter

And now we need to make a app.py file and copy paste the following code

app.py

import tkinter as tk
from tkinter import *
root = tk.Tk()
root.geometry("170x230")
root.title("Calculator")
root.maxsize(170,230)
root.minsize(170,230)

#Entry Widgets to show calculations
inp = Entry(root,width=16,borderwidth=3,relief=RIDGE)
inp.grid(pady=10,row=0,sticky="w",padx=15)


# <====================  Button Operation code starts here.. ==============>
def nine():
        inp.insert("end","9")

def eight():
        inp.insert("end","8")

def seven():
        inp.insert("end","7")

def six():
        inp.insert("end","6")

def five():
        inp.insert("end","5")

def four():
        inp.insert("end","4")

def three():
        inp.insert("end","3")

def two():
        inp.insert("end","2")

def one():
        inp.insert("end","1")

def zero():
        inp.insert("end","0")

def double_zero():
        inp.insert("end","00")

def dot():
        inp.insert("end",".")

def plus():
        inp.insert("end","+")

def minus():
        inp.insert("end","-")

def mul():
        inp.insert("end","*")

def divide():
        inp.insert("end","/")

def modulus():
        inp.insert("end","%")

def result():


        if inp.get() == "":
                inp.insert("end","error")
        elif inp.get()[0] == "0":
                inp.delete(0,"end")
                inp.insert("end","error")

        else:
                res = inp.get()
                res = eval(res)
                inp.insert("end"," = ")
                inp.insert("end",res)

def clear():
        inp.delete(0,"end")


# <============ end code ================>



# <============= Button Design Code starts here.. ==================>

clear = Button(root,text="C",width=2,command=clear,bg="red",fg="white",relief=RIDGE)
clear.grid(row=0,sticky="w",padx=125)


nine = Button(text="9",width=2,command=nine,borderwidth=3,relief=RIDGE)
nine.grid(row=1,sticky="w",padx=15)

eight = Button(text="8",width=2,command=eight,borderwidth=3,relief=RIDGE)
eight.grid(row=1,sticky="w",padx=45)

seven = Button(root,text="7",width=2,command=seven,borderwidth=3,relief=RIDGE)
seven.grid(row=1,sticky="w",padx=75)

plus = Button(root,text="+",width=2,command=plus,borderwidth=3,relief=RIDGE)
plus.grid(row=1,sticky="e",padx=125)


six = Button(text="6",width=2,command=six,borderwidth=3,relief=RIDGE)
six.grid(row=2,sticky="w",padx=15,pady=5)

five = Button(text="5",width=2,command=five,borderwidth=3,relief=RIDGE)
five.grid(row=2,sticky="w",padx=45,pady=5)

four = Button(root,text="4",width=2,command=four,borderwidth=3,relief=RIDGE)
four.grid(row=2,sticky="w",padx=75,pady=5)

minus = Button(root,text="-",width=2,command=minus,borderwidth=3,relief=RIDGE)
minus.grid(row=2,sticky="e",padx=125,pady=5)



three = Button(text="3",width=2,command=three,borderwidth=3,relief=RIDGE)
three.grid(row=3,sticky="w",padx=15,pady=5)

two = Button(text="2",width=2,command=two,borderwidth=3,relief=RIDGE)
two.grid(row=3,sticky="w",padx=45,pady=5)

one = Button(root,text="1",width=2,command=one,borderwidth=3,relief=RIDGE)
one.grid(row=3,sticky="w",padx=75,pady=5)

multiply = Button(root,text="*",width=2,command=mul,borderwidth=3,relief=RIDGE)
multiply.grid(row=3,sticky="e",padx=125,pady=5)


zero = Button(text="0",width=2,command=zero,borderwidth=3,relief=RIDGE)
zero.grid(row=4,sticky="w",padx=15,pady=5)

double_zero = Button(text="00",width=2,command=double_zero,borderwidth=3,relief=RIDGE)
double_zero.grid(row=4,sticky="w",padx=45,pady=5)

dot = Button(root,text=".",width=2,command=dot,borderwidth=3,relief=RIDGE)
dot.grid(row=4,sticky="w",padx=75,pady=5)

divide = Button(root,text="/",width=2,command=divide,borderwidth=3,relief=RIDGE)
divide.grid(row=4,sticky="e",padx=125,pady=5)

result = Button(root,text="=",width=10,command=result,bg="red",fg="white",borderwidth=3,relief=RIDGE)
result.grid(row=5,sticky="w",padx=15,pady=5)

modulus = Button(root,text="%",width=2,command=modulus,borderwidth=3,relief=RIDGE)
modulus.grid(row=5,sticky="e",padx=125,pady=5)

root.mainloop()

# <============ end code ==============>

And now if you execute this application by execute the below command

python app.py