PR0L1NE

Free · No sign-up · Runs in your browser

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About 6 MB, and only the first time: your browser keeps a copy.

Free, no sign-up, and it runs in your own browser: your code never leaves it.

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Python visualizer: see your code run, step by step

Write Python and step through it line by line, in a real CPython running in your browser. PR0L1NE draws every variable, list, dict, object and call frame as it changes, stacks each pass of a loop to compare, draws graphs and trees, and estimates time and space complexity. Free, no sign-up, and it runs in your own browser.

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