About OnlinePy
A privacy-first Python IDE that runs entirely in your browser. No servers, no ads, no accounts.
We believe coding should be accessible, private, and ad-free. Too many online compilers require accounts, show ads, or send your code to remote servers. OnlinePy is different — your code runs entirely in your browser, not on a remote server.
Technology
Powered by Pyodide, which compiles CPython to WebAssembly. Your code executes natively in the browser — no backend, no network round-trip. Uses SharedArrayBuffer for multi-threading and OPFS for package caching.
How it works
- 1.Pyodide compiles CPython to WebAssembly bytecode
- 2.Your browser runs this WASM module locally
- 3.Results display instantly — no network round-trip
Quick Guide
Write & Run
Type code in the editor. Click Run or press Ctrl+Enter. Output appears instantly below.
Handle Input
When your code calls input(), a prompt appears in the terminal. Type and press Enter.
Use Scientific Libraries
Import NumPy, Pandas, Matplotlib, SciPy, or scikit-learn directly. They install automatically.
import numpy as np # Create an array arr = np.array([1, 2, 3, 4, 5]) # Basic operations print(f"Mean: {np.mean(arr)}") print(f"Std: {np.std(arr)}") print(f"Sum: {np.sum(arr)}") # Matrix operations matrix = np.array([[1, 2], [3, 4]]) print(f"\nDeterminant: {np.linalg.det(matrix)}")
Visualize Data
Charts render inline. Just call plt.show().
import matplotlib.pyplot as plt import numpy as np x = np.linspace(0, 2 * np.pi, 100) plt.plot(x, np.sin(x)) plt.title("Sine Wave") plt.show()