Python Playground — Run Python in Your Browser

🐍 Python 3

# Welcome to the Python playground!
# Press Run (or Ctrl+Enter) to execute.
# First run loads the Python runtime (~8MB) — subsequent runs are instant.

# ── Variables & types ───────────────────────────────
name = "world"
count = 0

# ── Functions ───────────────────────────────────────
def greet(who: str) -> str:
    return f"Hello, {who}!"

print(greet(name))

# ── Lists & comprehensions ───────────────────────────
languages = ["Python", "JavaScript", "Go", "Rust"]
upper = [lang.upper() for lang in languages]
print("Languages:", ", ".join(upper))

# ── Dictionaries ────────────────────────────────────
user = {"name": "Ada", "age": 36, "active": True}
print(f"{user['name']} is {user['age']} years old.")

# ── Loops & accumulation ─────────────────────────────
for i in range(1, 6):
    count += i
print(f"Sum 1–5: {count}")

# ── Standard library ────────────────────────────────
import math, json, datetime
print(f"Pi: {math.pi:.4f}")
print(f"Today: {datetime.date.today()}")
data = json.dumps({"key": "value", "n": 42}, indent=2)
print(data)

Output

Press Run to load Python and execute…

Ctrl+Enter to run · First run downloads Pyodide (~8MB) and caches it · Code runs locally — never sent to a server

Try these examples

Click any example to load it into the editor above, then hit Run.

How this works

Pyodide is CPython — the standard Python interpreter — compiled to WebAssembly. When you press Run for the first time, the browser downloads Pyodide (~8MB) from a CDN and caches it. Every subsequent run is instant, even after refreshing the page.

The playground intercepts sys.stdout and sys.stderr using Python's io.StringIO, captures all print() output and error tracebacks, and displays them in the output pane. Your code runs entirely in your browser — nothing is sent to a server.

What's available: the full Python standard library — math, json, datetime, re, collections, itertools, functools, pathlib, dataclasses, typing, and more. Network calls (requests, urllib) won't work in the browser sandbox. NumPy and other scientific packages can be loaded via import micropip; await micropip.install('numpy') but require async execution.

What to try next

Python Foundations track — structured lessons from first principles
Python snippets — 14 copy-ready idiomatic patterns
Python language reference — deep dives on functions, OOP, and async
To-Do List project in Python — first real program to build