Write and run Python in your browser with a real interpreter behind it. The Monaco editor gives you Python syntax highlighting, find-and-replace, and formatting; the file explorer lets you build small multi-file scripts; and the standard-input panel feeds input() so interactive programs work too. Pick a starter example or paste your own code and see actual output — including full tracebacks when something raises.
Best Fit
- Try a Python language feature or a quick algorithm without opening an editor locally.
- Reproduce a small bug across two or three files and share the exact repro.
- Run a script that reads input, then read its output inline.
How to use Python Compiler
- Start from an example (Hello World, FizzBuzz, Fibonacci, and more) or write your own.
- Add files with the explorer if your script imports its own modules.
- If your code calls
input(), open the Input panel and add one line per read. - Press Run (or Ctrl+Enter) to execute; read the output and any traceback below.
- Copy the code, or download the file — multi-file scripts download as a zip.
What Python Compiler helps with
- Real Python execution that surfaces genuine output and tracebacks, not just red squiggles.
- Multi-file scripts with a file explorer, tabs, and search across files.
- Standard-input support so interactive
input()programs run as intended. - Quality-of-life editing: format, find and replace, word wrap, and editor themes.
Examples
Hello World
Input
print("Hello, World!")
Output
Hello, World!
Reading input with stdin
Input
name = input()
print(f"Hi {name}, your name has {len(name)} letters.")
Input panel:
Ada
Output
Hi Ada, your name has 3 letters.
Frequently Asked Questions
Where does my code run?
Your code is sent to the Parsepad backend, executed with a real Python interpreter in a sandbox, and the output is returned to your browser. Unlike a purely client-side tool, running requires a network round-trip — which is what lets it report genuine interpreter output and tracebacks.
Can I run programs that read input?
Yes. Open the Input panel from the status bar and enter one line for each input() call your program makes. The lines are fed to standard input in order when you run.
Does it support multiple files?
Yes. Use the file explorer to add modules across several .py files. When you download a multi-file script it is packaged as a zip so the structure is preserved.
Which Python version is used?
A current Python 3 runtime. Standard-library modules are available; network access, platform-specific operations, and long-running tasks are limited by the execution sandbox.
Are there limits on program size or run time?
Yes, and they are the same for every visitor. All your files together may total 60,000 characters, and the Input panel accepts up to 20,000 characters of standard input. A program is stopped after 10 seconds of run time, and the whole request is capped at 15 seconds. A submission over a size limit is reported in the console instead of being run; a program stopped at the time limit reports Execution timed out.
