JSON syntax error guide

JSON Property Names Must Be Double-Quoted: What It Means and How to Fix It

Unlike JavaScript object literals, JSON requires every object key to be a double-quoted string. Bare identifiers such as name, userId, or enabled are invalid JSON.

What this JSON error means

Typical parser message

SyntaxError: Expected property name or } in JSON

Inside every JSON object, the token after { or , must be either a double-quoted property name or the closing }. Quote every bare property key.

Broken JSON vs. corrected JSON

Compare the invalid syntax with a corrected version before applying the same change to your payload.

Invalid JSON

{name:"Ada", active:true}

Valid JSON

{"name":"Ada", "active":true}

Common causes of this JSON error

●Copying a JavaScript object literal
●Writing configuration by hand
●Assuming simple identifier keys do not need quotes
●Converting from YAML without a real serializer

Fix and validate your JSON

After correcting the suspected syntax, run the complete payload through a validator. If it still fails, use the diagnostic tool to locate the next parser error before formatting the final JSON.

Check JSON for errors Fix invalid JSON JSON Validator JSON Formatter

Related JSON errors

JSON Unexpected Token Error

Understand and fix JSON unexpected token errors. See broken and corrected examples, common causes, and a fast workflow for finding the exact invalid character.

Unexpected End of JSON Input

Fix “Unexpected end of JSON input” errors caused by truncated JSON, missing braces or brackets, incomplete strings, and empty API responses.

Trailing Comma in JSON

Learn why trailing commas are invalid in standard JSON and fix objects or arrays copied from JavaScript, TypeScript, JSON5, or configuration files.

Single Quotes in JSON

Fix invalid JSON that uses single quotes. JSON requires double quotes around property names and string values.

Invalid Escape Character in JSON

Fix invalid JSON escape sequences in Windows paths, regex strings, copied text, and backslash-heavy values.

Comments Are Not Allowed in JSON

Learn why // and /* */ comments make strict JSON invalid, and when to use JSONC, JSON5, or separate metadata instead.

JSON error FAQ

What does JSON Property Names Must Be Double-Quoted mean?

Unlike JavaScript object literals, JSON requires every object key to be a double-quoted string. Bare identifiers such as name, userId, or enabled are invalid JSON.

How do I fix JSON Property Names Must Be Double-Quoted?

Inside every JSON object, the token after { or , must be either a double-quoted property name or the closing }. Quote every bare property key.