Turn a JavaScript object literal into valid JSON

Console output, fixtures and config snippets quote keys only sometimes and use single quotes. Strict JSON parsers reject all of it — this rewrites it properly.

Tools used in this guide

The job

You copied {a: 1, b: 'x'} out of a console.log and JSON.parse refuses it. Unquoted keys, single quotes, trailing commas and undefined are all legal JavaScript and all illegal JSON — converting by hand is where mistakes creep in.

Paste the literal

Paste the object or array literal; the parser handles unquoted keys, single and template-free string quotes, comments, trailing commas, and numeric forms like .5 or 0x1F. Output is strict, double-quoted, pretty-printed JSON.

undefined entries are dropped, matching what JSON.stringify would produce.
NaN and Infinity have no JSON representation and are reported rather than guessed.

Not an evaluator

The input is parsed as a literal, not executed — functions, spread syntax, variables and computed keys are rejected. That's deliberate: it means pasting code can never run anything. Limit: 1,000,000 characters.