Python Docs

Introduction to Flask & Django

Flask and Django are the two most widely used Python web frameworks. Both help you build web applications, APIs, dashboards, and backend services — but they follow different philosophies. This page explains their concepts, differences, and use cases with examples.

What is a Python Web Framework?

A web framework helps developers build web applications faster by providing tools like routing, templates, database handling, and security features. Instead of writing everything from scratch, you use a framework to structure your application.

Handle HTTP requests & responses
Manage URLs & routing
Connect with databases
Render HTML templates
Provide security layers (CSRF, authentication)

Flask (Micro Framework)

Flask is minimal and lightweight. You start with a small core and add extensions only when needed. Perfect for beginners, APIs, and small to medium-sized applications.

Lightweight and very flexible
No predefined project structure
Choose your own database, ORM, authentication library, etc.
Great for REST APIs and microservices

Flask Example

pip install flask

from flask import Flask
app = Flask(__name__)

@app.get('/')
def home():
    return 'Hello Flask'

if __name__ == '__main__':
    app.run(debug=True)

Flask is best for:

REST APIs
Microservices
IoT dashboards
Small to medium web applications
Prototyping ideas quickly

Django (Full-Stack Framework)

Django is a high-level framework following the “batteries included” philosophy. It includes everything you need to build a complete application: ORM, admin panel, authentication, forms, and more.

Built-in admin panel
Powerful ORM with migrations
Authentication, permissions, security
Convention over configuration
Excellent for large, scalable enterprise apps

Django Example

pip install django
django-admin startproject mysite
cd mysite
python manage.py runserver

Django is best for:

Large enterprise-level applications
E-commerce websites
Social networks (e.g., Instagram uses Django)
Large admin dashboards
Secure authentication systems

Comparison

Key differences between Flask and Django:

Feature	Flask	Django
Learning Curve	Easy	Moderate
Setup Time	Fast	Medium
Built-in Admin	No	Yes
ORM	Optional	Built-in
Best For	APIs, Small Apps	Large Apps

Summary

Flask is perfect when you want flexibility and minimal setup. Django is ideal for large, structured applications with built-in features. Both are powerful — choose based on your project requirements.