JSON Validator Online

Validate JSON syntax in real-time. Detect missing quotes, unexpected tokens, trailing commas, and bracket mismatches instantly.

Format, beautify, and clean up messy JSON data with customizable spacing and expanded editor view.

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In: 1 lines (200 chars)

Indentation Spacing:

Raw Unformatted JSON1 lines

Formatted Output

Common JSON Syntax Errors & How to Fix Them

Trailing Commas: JSON spec standard disallows commas after the final key-value pair in an object or array.
Single Quotes: JSON keys and string values MUST use double quotes (`"`). Single quotes (`'`) are invalid syntax.
Unquoted Keys: Object keys like { name: "John" } are invalid in JSON. Keys must be enclosed in double quotes: { "name": "John" }.

Check out our JSON Schema Validator to enforce required fields and type constraints.