Python in your browser

Online Python Compiler

Write and run Python code without installing anything. Processing happens in your browser with CPython and WebAssembly.

Your code is not sent to our server

Example

Python code

# Run Python directly in your browser
language = "Python"
numbers = [2, 4, 6]
print(f"Hello, {language}!")
print("Sum:", sum(numbers))

Shortcut: Ctrl + Enter or Cmd + Enter to run. Tab inserts four spaces.

Input (stdin)

Each input() call consumes one line. Python raises EOFError when no lines remain.

Output

Program output will appear here.

How to use the online Python compiler

The editor is designed for quick tests, exercises, and examples from our tutorials.

Write the code

Type or paste a Python program into the editor. Your code is saved only in this browser.
Provide input

If the program uses input(), put each answer on a separate line in the input field.
Run and review

Select Run to see printed output, warnings, and errors with the Python traceback.

Real Python powered by WebAssembly

This page is called a Python compiler because that is the common search term. Technically, it loads CPython through Pyodide and runs the program inside a browser Web Worker.

What works

Python syntax and the standard library.
input(), stdout, stderr, and Python tracebacks.
Imports for packages available in Pyodide, including NumPy and pandas, downloaded on demand.
Stopping long-running loops without freezing the page interface.

Important limitations

Packages that require services, unsupported native binaries, or operating-system resources may not work.
Files and variables from an execution are not retained after the environment restarts.
The Worker protects page responsiveness, but it does not make unknown code trustworthy.

Privacy and loading

Your code, input, and output stay on your device. Only after you select Run does the browser download Pyodide 0.29.4 and required libraries from the jsDelivr CDN. Your program content is not included in those requests.

Documentation and next steps

Go deeper into the concepts used in the editor with Universo Python guides and technical references maintained by the official projects.

Related guides

Python variables and data types
Understand names, values, numbers, strings, lists, and type conversions.
Control flow: if, for, and while
Build decisions and loops to move beyond your first examples.
Functions in Python
Organize programs into reusable blocks with parameters and return values.
Error handling with try and except
Learn to read exceptions and handle expected failures in a program.

Official references

Official Python tutorial (Official documentation)
An introduction to the language, data structures, modules, input, output, and exceptions.
input() function documentation (Official documentation)
Reference for text input and the EOFError raised when no lines remain.
Pyodide 0.29.4 documentation (Official documentation)
Details about CPython on WebAssembly, compatibility, and packages available in the browser.

Frequently asked questions

Do I need to install Python?

No. A CPython runtime compiled to WebAssembly is loaded in the browser when you run your first program.

Is my code sent to the server?

No. Code, input, and output stay in the browser. The CDN receives only requests for public Pyodide files and imported packages.

Can I use NumPy and pandas?

Yes. Packages included in the Pyodide distribution are detected from imports and downloaded on demand. Some native or operating-system-dependent packages are not compatible.

Why can the first run take longer?

On the first run, the browser must download and initialize the Python runtime. Later runs in the same session reuse the loaded environment.

Online Python Compiler