Backend and APIs · Comparison
FastAPI vs Django vs Flask
Three widely used Python web frameworks. Django includes almost everything, Flask includes almost nothing, and FastAPI focuses on typed, self-documenting APIs.
3 options · 8 questions side by side · updated
| Compare | FastAPI | Django | Flask |
|---|---|---|---|
| What it is | Async framework for typed APIs | Full-stack, batteries included | Minimal micro-framework |
| Built on | Starlette, Pydantic, ASGI | Its own stack, on WSGI or ASGI | Werkzeug and Jinja, on WSGI |
| Database | Bring your own (SQLAlchemy, SQLModel) | Built-in ORM and migrations | Bring your own (Flask-SQLAlchemy) |
| Admin panel | None | Built in | Through extensions |
| API docs | Automatic OpenAPI and Swagger UI | Through DRF or Django Ninja | Through extensions |
| Async | Native | Supported, still maturing | Limited |
| Learning curve | Low for APIs | Steeper, many conventions | Lowest to start |
| Best for | JSON APIs and AI model serving | Content sites, marketplaces, back offices | Small apps, webhooks, prototypes |
How to choose between FastAPI, Django and Flask
- Pick FastAPI for JSON APIs, especially ones that serve Python AI or data code.
- Pick Django when the product needs an admin panel, accounts and a database layer from day one.
- Pick Flask for small services and prototypes where a tiny, flexible core is enough.
The options
- FastAPIA Python framework for building APIs where ordinary type hints do the validation and interactive documentation is generated automatically.
- DjangoA 'batteries included' Python web framework with its own database layer, admin panel, user accounts and security protections ready from day one.
- FlaskA small, flexible Python web framework that handles routing and requests and leaves every other choice to you.
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