paste & scan
node:vm sandbox · BCD cross-ref

Will your code hold up across the spec?

Paste a snippet. The checker parses it with acorn, executes it in a sandboxed node:vm context, and logs every identifier — then cross-references BCD across Chrome, Safari, Firefox, and Edge. Deprecation flags and removed-API dates surface with a link back to the spec section.

Paste & scan
Runs in a sandboxed VM. No network, no host globals, 50 KB cap, 1 s budget.

Runs in a sandboxed node:vm context — no network, no host globals.

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Paste JavaScript above and hit Scan. We trace every identifier — parse-time and runtime — and cross-reference BCD across Chrome, Safari, and Firefox.