Best Python IDE for FastAPI Development

The best Python IDE for FastAPI: VS Code or PyCharm Pro, how to debug a route, test with pytest, and set up linting and type checking for Pydantic.

For FastAPI, use VS Code with the Python extension if you want a free setup, or PyCharm Pro if you want FastAPI-aware tooling built in. Both can run Uvicorn under a debugger, run pytest, and work with Ruff and a type checker. The framework itself needs little from the editor, so the real decisions are debugging, testing and type checking.

At a glance

What a FastAPI developer needs from an editor

1. Run the server and reload on change. That is Uvicorn: uvicorn main:app --reload.
2. Hit breakpoints inside your routes. The debugger should start the app and stop in your code when a request arrives.
3. Check types. Pydantic models and function signatures are what FastAPI validates against, so catching type errors early prevents real bugs.
4. Run tests quickly. pytest with FastAPI’s TestClient.
5. Lint and format. Ruff covers both.

VS Code

VS Code’s FastAPI tutorial requires the Python extension, and recommends Pylance for type checking with Pydantic and FastAPI. The workflow it describes:

1. Create a project folder, with a requirements.txt listing fastapi and uvicorn.
2. Run the Python: Create Environment command, choose Venv, and select requirements.txt so the dependencies install automatically.
3. Press F5 and select FastAPI. That configuration runs Uvicorn through the debugger, and the terminal shows the server address (by default http://127.0.0.1:8000/).
4. To use a different port, run Debug: Add Configuration, choose Python Debugger and then FastAPI. That creates .vscode/launch.json. Add "--port=5000" to "args" and restart the debugger.

To debug a route, click the margin next to a line (or press F9) to set a breakpoint, press F5, open /docs, expand a route, choose Try it out and then Execute. The debugger stops at the breakpoint. Inspect values in the Variables view, or select an expression and choose Evaluate in Debug Console. Stop the debugger with Shift+F5.

PyCharm

JetBrains’ PyCharm has free core features, and says that advanced Django, Flask and FastAPI support is part of PyCharm Pro, along with remote development over SSH, WSL or Docker and database tools for more than 40 databases. If you build FastAPI services that talk to databases or run in containers, Pro is the stronger fit. The free tier still runs and debugs Python, runs tests and includes Git.

Debugging in any editor

FastAPI’s own documentation shows an approach that works in every editor: call Uvicorn from your file.

import uvicorn
from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def root():
    a = "a"
    b = "b" + a
    return {"hello world": b}


if __name__ == "__main__":
    uvicorn.run(app, host="0.0.0.0", port=8000)

Because the server starts from your code, you can run the file in the debugger and it stops at your breakpoints. The __name__ == "__main__" check means uvicorn.run only executes when you run the file directly, not when another file imports app. In VS Code, run Python: Current File (Integrated Terminal) from the debug panel; in PyCharm, use Run > Debug on the file.

Testing

FastAPI tests use Starlette’s TestClient with pytest. Tested on 4 November 2026 with FastAPI 0.162.0 and Starlette 1.10.0, TestClient emits a deprecation warning when only httpx is installed (“install httpx2 instead”), and the example below passes without a warning once httpx2 is installed. FastAPI’s own testing page may still name httpx, so check which one your versions expect:

uv add --dev httpx2 pytest

from fastapi import FastAPI
from fastapi.testclient import TestClient

app = FastAPI()


@app.get("/")
async def read_main():
    return {"msg": "Hello World"}


client = TestClient(app)


def test_read_main():
    response = client.get("/")
    assert response.status_code == 200
    assert response.json() == {"msg": "Hello World"}

FastAPI’s documentation notes that test functions are normal def, not async def, and that client calls don’t use await, so pytest works directly. Test function names must start with test_. VS Code’s Python extension supports testing with unittest and pytest, and pytest works from the terminal in any editor. See pytest vs unittest for the framework choice.

Type checking and linting

FastAPI leans on type hints, so a type checker is worth wiring up in whichever editor you pick. mypy, Pyright, ty and Pyrefly are compared in Python type checkers compared, and Python type hints: a practical guide covers the habit itself. Ruff ships a language server (ruff server) that provides diagnostics, code actions and formatting in any editor that supports the language server protocol, and Ruff’s documentation also recommends the ty language server for navigation and autocompletion.

Async code

FastAPI routes can be def or async def. If you are new to the async model, Python async/await explained covers it.

Which should you pick?

• Free, light, and you want to start now: VS Code with the Python extension and Pylance.
• FastAPI plus databases, containers or remote machines: PyCharm Pro.
• Already use PyCharm’s free tier: keep it. Debug with the uvicorn.run approach above.
• You prefer a terminal editor: Neovim works with a language server and Ruff; see the best Python IDEs.

Once the app works locally, see Docker for Python with uv for packaging it, and Gunicorn vs Uvicorn vs Hypercorn for running it in production. For the framework itself, see FastAPI and Django vs FastAPI vs Flask.