Python in your browser

Real CPython via WebAssembly.

Run code, load packages with micropip, and inspect the machine — nothing to install, nothing leaves the page.

Python regex, live

Matches, groups, flags, substitution.

Test Python regular expressions and watch matches, spans, capture groups, flags, and a substitution preview update live.

Format & validate JSON

Pretty-print, minify, sort keys.

Pretty-print, minify, sort keys, and validate JSON with Python's json module — all in-browser.

Markdown → HTML

Real Python markdown via micropip.

Convert Markdown to HTML with the real Python markdown package, loaded on demand through Pyodide and micropip.

Unified text diffs

Compare two blocks with difflib.

Compute unified diffs between two blocks of text with Python's difflib — paste, compare, and copy the result.