Unquoted Keys in JSON: The Fix

Quick answer: In JSON, every property name must be a double-quoted string — {"name": "Dana"}, never {name: "Dana"}. Unquoted keys are valid JavaScript but invalid JSON, so JSON.parse() throws. The fix is to wrap every key in double quotes. The JSON Trimmer adds the missing quotes and returns strict JSON.

JavaScript object literals let you drop the quotes on keys that are valid identifiers:

{ name: "Dana", role: "admin", age: 30 }

That's fine in a .js file but not in JSON. The error is usually Expected property name or '}' in JSON (or Unexpected token n in JSON), pointing at the first unquoted key. Strict JSON needs:

{ "name": "Dana", "role": "admin", "age": 30 }

JSON treats keys as plain strings, full stop. JavaScript identifiers have rules (no spaces, can't start with a digit, reserved words, etc.), and JSON deliberately avoids importing any of that complexity. Requiring quotes means a key can be any string — "first name", "123", "@type" — and every parser handles it identically. This is the same design philosophy behind single double-quotes only and no trailing commas.

It also means keys that aren't legal identifiers are perfectly legal JSON keys:

{ "full name": "Dana Lee", "2fa": true, "x-api-version": "1.0" }

None of those could be unquoted in JavaScript, but all are valid quoted JSON keys.

• Quickly: paste the object into the JSON Trimmer, which quotes bare keys (and strips comments and trailing commas) to produce strict JSON.
• In code, don't hand-write it. Serialize from data so quoting is automatic:

const obj = { name: "Dana", role: "admin" };
JSON.stringify(obj);   // {"name":"Dana","role":"admin"}

JSON.stringify() always double-quotes keys, so generating JSON from objects sidesteps the problem entirely — see Parse and Stringify.

Unquoted keys most often sneak in from config files written in relaxed dialects. If you genuinely want bare keys, comments, and trailing commas, use JSON5 or JSONC on purpose with a parser that supports them — not JSON.parse(). See JSON5 vs JSONC for when each is appropriate. When you need strict JSON, validate the result with the JSON Validator.

Do JSON keys need quotes? Yes. Every property name in JSON must be a double-quoted string. Unquoted keys are invalid and cause a parse error.

Why is {name: "x"} valid in JavaScript but not JSON? JavaScript object literals allow unquoted keys that are valid identifiers. JSON is a stricter data format that treats all keys as strings, so it requires quotes around every one.

How do I add quotes to all my keys at once? Use a JSON5-aware cleaner like the JSON Trimmer, or re-serialize the data with JSON.stringify() (JS) or json.dumps() (Python), which quote keys automatically.

Can a JSON key contain spaces or start with a number? Yes — as long as it's quoted. "first name" and "2fa" are valid JSON keys even though they couldn't be unquoted JavaScript identifiers.