FREE · DEVELOPER TOOLS
Online Python Compiler.
Write and run Python 3 code in your browser with no install or account: output, errors, input() values, examples, .py download and share links.
Program input (stdin): one line per input() call
Press Run to see the output here.Python 3.14 by Pyodide (MPL-2.0) in WebAssembly. Standard library only (math, json, re, datetime, collections, dataclasses…); packages such as numpy and network access are not available. Stop restarts Python, which clears variables.
How to use Online Python Compiler
Type or paste Python code and press Run (Ctrl+Enter). Put the values your program reads with input() in Program input, one per line. Stop restarts Python.
How it works
Runs CPython 3.14 compiled to WebAssembly by Pyodide (MPL-2.0) in a background worker on your device; your code and its input never leave the browser. Share links store the code inside the link.
Example
The Fibonacci example prints the first 15 numbers and fib(300); the Hello example reads a name from Program input and greets it.
Run Python code in your browser
- Type or paste your code in main.py, or pick a program in
Example. - If your program calls input(), open
Program input (stdin)and write one value per line. - Press
Run (Ctrl+Enter). The output appears below; errors are shown in red with the line of main.py that failed. - Press
Stopto end a program that runs too long, thenDownload .pyorCopy share linkto keep your code.
The first run downloads Python (about 12 MB) once; after that the browser keeps it in its cache. Your code is saved in this browser so it is still there when you come back.
What works and what does not
This is CPython 3.14 with its standard library: math, random, re, json, csv, datetime, collections, itertools, dataclasses, decimal, fractions, statistics and more. Packages such as numpy, pandas or requests are not available, there is no network access and no graphical window, so turtle and tkinter programs cannot be shown.
Stop restarts Python, which clears variables from previous runs. To test a regular expression interactively, try the Regex Tester; to explore data with SQL instead, use SQL Query on CSV & JSON Files.
Questions about Online Python Compiler
Is my code sent to a server?
No. Python runs as WebAssembly in a background worker of your browser. A share link stores the code inside the link itself.
Why does input() not wait for me to type?
The program runs in the background, so it reads the lines you wrote in Program input, one per input() call. When the lines run out, input() raises EOFError.
Can I install packages with pip?
No. Only the standard library is included, so the tool never downloads code from other servers.
Is Online Python Compiler free, and do I need an account?
Yes. This tool is free to use in your browser without an account. Processing takes place on your device.
What are the limits and what should I check?
Python 3.14 standard library only: packages such as numpy or pandas, network access and graphical windows are not available. The first run downloads about 12 MB, then the browser caches it. Review the result before using it in your work.
Is my input sent to a server?
Your input is processed in your browser and is not uploaded by this tool. Files and pasted text are cleared when the page is refreshed. Normal website requests are still required to load the page and its libraries. Read the privacy explanation.