Python Tkinter vs PyQt

Building a desktop application in Python is an exciting journey, but the first hurdle is always choosing the right library.

I have spent years building custom tools and internal dashboards using Python, and I have spent most of that time working with Tkinter.

However, I’ve also had my fair share of projects where PyQt was the better fit for the job.

In this guide, I will share my firsthand experience with both frameworks to help you decide which one suits your next project.

Table of Contents

Why Choosing the Right GUI Framework Matters

When I first started developing desktop apps, I thought any library would do as long as it showed a window.

I quickly learned that the framework you choose affects your development speed, the app’s look, and even how you distribute it.

If you are building a simple calculator for a local US tax office, you might not need a heavy framework.

But if you are designing a high-end data visualization tool for a tech firm in San Francisco, aesthetics and performance become critical.

An Overview of Tkinter

Tkinter is Python’s built-in library for creating interfaces. It is the “Standard GUI” for Python.

I love Tkinter because I don’t have to install anything extra; it comes bundled with my Python installation.

It uses a “wrapper” around the Tcl/Tk engine, which has been around for decades.

The Pros of Tkinter

Zero Installation: Since it’s built-in, your users won’t need to run pip install for the GUI to work.
Lightweight: It starts up almost instantly and consumes very little RAM.
Simplicity: The syntax is easy, making it perfect for beginners or quick internal tools.

The Cons of Tkinter

Dated Look: By default, Tkinter apps look like software from the Windows 95 era.
Limited Widgets: You won’t find advanced widgets like built-in web browsers or complex charts.

An Overview of PyQt

PyQt is a Python binding for the Qt framework, which is written in C++. It is a powerhouse.

When I need to build a professional-grade application that looks like a modern Mac or Windows app, I reach for PyQt.

It offers a massive library of widgets and tools that go far beyond simple buttons and text boxes.

The Pros of PyQt

Modern Aesthetics: It follows the native look and feel of the operating system perfectly.
Feature Rich: It includes tools for networking, database management, and multimedia.
Qt Designer: You can drag and drop elements to design your UI visually rather than writing every line of layout code.

The Cons of PyQt

Steep Learning Curve: There are many more classes and methods to learn compared to Tkinter.
Large Footprint: It adds a significant size to your final executable file.
Licensing: If you are building a commercial closed-source app, you might need to buy a license.

Method 1: Build a Simple US Sales Tax Calculator in Tkinter

I often use Tkinter for small utility apps. Let’s look at how I would build a Sales Tax Calculator tailored for a business in Florida (7% tax).

Tkinter uses a “Grid” system for layouts, which I find very intuitive for forms.

import tkinter as tk
from tkinter import messagebox

def calculate_tax():
    try:
        # Get input amount
        amount = float(entry_amount.get())
        # Florida Sales Tax (6% State + 1% typical local)
        tax_rate = 0.07
        total_tax = amount * tax_rate
        final_total = amount + total_tax
        
        # Display results
        label_result.config(text=f"Total with Tax: ${final_total:,.2f}")
    except ValueError:
        messagebox.showerror("Input Error", "Please enter a valid numeric amount.")

# Initialize the main window
root = tk.Tk()
root.title("Florida Sales Tax Tool")
root.geometry("400x250")

# Adding widgets
tk.Label(root, text="Enter Sale Amount ($):", font=("Arial", 12)).pack(pady=10)
entry_amount = tk.Entry(root, font=("Arial", 12))
entry_amount.pack(pady=5)

btn_calculate = tk.Button(root, text="Calculate Tax", command=calculate_tax, bg="#0078d4", fg="white")
btn_calculate.pack(pady=20)

label_result = tk.Label(root, text="Total with Tax: $0.00", font=("Arial", 12, "bold"))
label_result.pack(pady=10)

# Start the application
root.mainloop()

You can see the output in the screenshot below.

When I run this, the window is simple. It gets the job done without any fuss. If you are working on a tight deadline for a “one-off” internal script, this is the way to go.

Method 2: Build a Real Estate Commission Tracker in PyQt6

Now, let’s look at how PyQt handles a slightly more complex UI. Imagine you are a real estate agent in New York, and you want a sleek app to track commissions.

PyQt uses a “Signals and Slots” mechanism for handling button clicks, which is more robust for large apps.

import sys
from PyQt6.QtWidgets import QApplication, QWidget, QVBoxLayout, QLabel, QLineEdit, QPushButton, QMessageBox

class CommissionApp(QWidget):
    def __init__(self):
        super().__init__()
        self.init_ui()

    def init_ui(self):
        # Set Window Properties
        self.setWindowTitle('NY Real Estate Commission Tracker')
        self.setGeometry(100, 100, 400, 300)

        # Create Layout
        layout = QVBoxLayout()

        # Create Widgets
        self.label_instr = QLabel('Enter Property Sale Price ($):')
        self.input_price = QLineEdit()
        self.input_price.setPlaceholderText("e.g. 750000")
        
        self.btn_calc = QPushButton('Calculate 6% Commission')
        self.btn_calc.clicked.connect(self.calculate_commission)
        # Styling the button
        self.btn_calc.setStyleSheet("background-color: #2c3e50; color: white; padding: 10px;")

        self.result_label = QLabel('Commission Amount: $0.00')
        self.result_label.setStyleSheet("font-size: 18px; color: green;")

        # Add Widgets to Layout
        layout.addWidget(self.label_instr)
        layout.addWidget(self.input_price)
        layout.addWidget(self.btn_calc)
        layout.addWidget(self.result_label)

        self.setLayout(layout)

    def calculate_commission(self):
        try:
            price = float(self.input_price.text())
            commission = price * 0.06
            self.result_label.setText(f'Commission Amount: ${commission:,.2f}')
        except ValueError:
            QMessageBox.critical(self, "Error", "Please enter a valid property price.")

if __name__ == '__main__':
    app = QApplication(sys.argv)
    window = CommissionApp()
    window.show()
    sys.exit(app.exec())

You can see the output in the screenshot below.

In this PyQt example, you can see the object-oriented approach I usually take. It feels more organized, especially as the application grows to include multiple windows.

Performance and Resource Consumption

In my experience, Tkinter is the king of low-resource environments.

If you are running an app on an old laptop or a Raspberry Pi, Tkinter will be much smoother.

PyQt, being based on C++, is very fast once it’s loaded, but it has a heavier memory footprint.

For most modern US desktops with 16GB of RAM, this difference is negligible.

Ease of Learning: Firsthand Observations

When I teach junior developers, I always start them with Tkinter.

The concepts of “root”, “main loop”, and “pack” can be learned in a single afternoon.

PyQt requires an understanding of Classes and Inheritance, which can be a bit daunting for beginners.

However, once you master PyQt, you feel like you have a “superpower” for building any software imaginable.

Deployment: Share Your App

Sharing your Python app with a client in Chicago or LA requires turning your script into an .exe file.

I use PyInstaller for both frameworks.

Tkinter apps result in very small executable files (around 10-15 MB).

PyQt apps often result in larger files (over 50 MB) because they have to include the Qt libraries.

Customization and Styling

If your brand has a specific color palette (like the red and white of a Coca-Cola themed app), styling is key.

In Tkinter, I find styling to be a bit tedious; you have to change colors widget by widget.

In PyQt, I can use “Qt Style Sheets” (QSS), which are very similar to CSS used in web design.

This allows me to style the entire app with just a few lines of code.

Summary of Key Differences

Feature	Tkinter	PyQt
Ease of Use	Very Easy	Moderate to Hard
Aesthetics	Basic/Old	Modern/Native
Installation	Built-in	Needs pip install
Learning Curve	Low	High
Visual Design	Manual code	Qt Designer (Drag & Drop)

In this article, I have shared my personal journey using both Tkinter and PyQt.

While I often use Tkinter for quick internal tools that stay on my machine, I prefer PyQt for anything that a client will see.

Choosing between them really depends on your specific needs and how much time you have to learn the framework.

If you want something built-in and simple, go with Tkinter. If you want a professional look and more features, PyQt is worth the effort.