A JavaScript scratchpad with a real console
Your code runs in a dedicated Web Worker, isolated from this page. console.log, console.error and returned values appear in the console pane, objects are pretty-printed, and await works at the top level.
The worker is terminated if a run exceeds 20 seconds, so a runaway loop never locks the tab.
Frequently asked questions
Can I use the DOM?
Not here — workers have no document. Use the HTML / CSS / JS playground for anything visual.
Which JavaScript version is supported?
Whatever your browser supports, which for current browsers means the latest ECMAScript features.
Related tools
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- Python data sandboxNumPy and pandas, loaded on demand, running locally.
- TypeScriptTranspiled by the real TypeScript compiler, then executed.
- LuaLua 5.3 on the Fengari VM.
- SQL (SQLite)A real SQLite engine in WebAssembly — fresh database every run.
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