Welcome folks today in this blog post we will be building a login and register system in python using tkinter. All the full source code of the application is shown below.

Get Started

In order to get started you need to make an app.py file and copy paste the following code

app.py

from tkinter import *

from tkinter import messagebox

import os

def register_user():
    username_info=username.get() 
    password_info=password.get()
    file=open(username_info,"w")
    file.write(username_info+"\n")
    file.write(password_info)
    file.close()
    u_entry.delete(0, END)
    p_entry.delete(0, END)
    messagebox.showinfo("info","Registration Successful")
    
def login_verify():
    username1=username_verify.get()
    password1=password_verify.get()
    u_entry1.delete(0, END)
    p_entry1.delete(0, END)
    list_of_files=os.listdir()
    if username1 in list_of_files:
        file1=open(username1,"r")
        verify=file1.read().splitlines()
        if password1 in verify:
            messagebox.showinfo("info","Login Successfull!!")
        else:
            messagebox.showinfo("info","Password has not been recognised")
    else:
        messagebox.showinfo("info","User not found")

def register():
    global username,password
    global u_entry,p_entry,root1
    root1=Toplevel(root)
    username=StringVar()
    password=StringVar()
    root1.title("Register")
    root1.configure(bg="#F1C40F")
    w1=350
    h1=310
    root1.geometry("%dx%d+%d+%d" %(w1,h1,x,y))
    Label(root1,text="Please enter the details below\nin the given empty fields",font=("Georgia",15),bg="#F9E79F").pack()
    Label(root1,text="",bg="#F1C40F").pack()
    Label(root1,text="Username *",font=("Georgia",15),bg="#F9E79F").pack()
    Label(root1,text="",bg="#F1C40F").pack()
    u_entry=Entry(root1,textvariable=username,width="15",borderwidth=3)
    u_entry.pack()
    Label(root1,text="",bg="#F1C40F").pack()
    Label(root1,text="Password *",font=("Georgia",15),bg="#F9E79F").pack()
    Label(root1,text="",bg="#F1C40F").pack()
    p_entry=Entry(root1,textvariable=password,width="15",borderwidth=3)
    p_entry.pack()
    Label(root1,text="",bg="#F1C40F").pack()
    button=Button(root1,text="Register",width=10,command=lambda:register_user(),bg="#F9E79F",font=("Georgia",12)).pack()
    root1.mainloop()

def login():
    global root2,u_entry1,p_entry1
    global username_verify,password_verify
    username_verify=StringVar()
    password_verify=StringVar()
    root2=Toplevel(root)
    w2=350
    h2=250
    root2.geometry("%dx%d+%d+%d" %(w2,h2,x,y))
    root2.configure(bg="#AF7AC5")
    root2.title("Login")
    Label(root2,text="Username",bg="#D7BDE2",font=("Georgia",17)).pack()
    Label(root2,text="",bg="#AF7AC5").pack()
    u_entry1=Entry(root2,textvariable=username_verify,width=15,borderwidth=3)
    u_entry1.pack()
    Label(root2,text="",bg="#AF7AC5").pack()
    Label(root2,text="Password",bg="#D7BDE2",font=("Georgia",17)).pack()
    Label(root2,text="",bg="#AF7AC5").pack()
    p_entry1=Entry(root2,textvariable=password_verify,width=15,borderwidth=3)
    p_entry1.pack()
    Label(root2,text="",bg="#AF7AC5").pack()
    button1=Button(root2,text="Login",width=10,command=lambda:login_verify(),bg="#D7BDE2",font=("Georgia",13)).pack()
    root2.mainloop()
    
def mainscreen():
    global root,screen_w,screen_h,x,y
    root=Tk()
    screen_w=root.winfo_screenwidth()
    screen_h=root.winfo_screenheight()
    w=350
    h=200
    x=screen_w/2.7
    y=screen_h/2.7
    root.geometry("%dx%d+%d+%d" %(w,h,x,y))
    root.title("Register-Login")
    root.configure(bg="#1ABC9C")
    heading=Label(root,text="Register/Login Form",font=("Georgia",18),bg="#A3E4D7").pack()
    Label(root,text="",bg="#1ABC9C").pack()
    login_button=Button(root,text="Login",width="300",font=("Georgia",15),bg="#A3E4D7",command=lambda:login()).pack()
    Label(root,text="",bg="#1ABC9C").pack()
    register_button=Button(root,text="Register",width="300",font=("Georgia",15),bg="#A3E4D7",command=lambda:register()).pack()
    Label(root,text="",bg="#1ABC9C").pack()
    root.mainloop()
mainscreen()

Now if you execute the python script by typing the below command as shown below

python app.py