JSON Validator Online – Debug & Format json validator
Validate JSON data with detailed error messages and path highlighting.
JSON Input
Validation Result
Valid JSON
Your JSON structure is syntactically correct.
What is an Online JSON Validator?
JSON (JavaScript Object Notation) is a strict data format. Even a single missing comma or a stray single quote can cause an entire application to crash. Our JSON Validator is designed to catch these errors instantly. It parses your input in real-time and provides meaningful feedback if something is wrong.
Unlike simple formatters, this tool focuses on syntactic correctness. It's the first step every developer should take when debugging an API response or a config file that "just won't work."
Common JSON Errors
- Trailing Commas: JSON does not allow a comma after the last element in an object or array.
- Single Quotes: All keys and string values must be enclosed in double quotes ("). Single quotes (') are invalid.
- Missing Quotes: Keys must always be quoted in valid JSON.
- Unescaped Characters: Special characters like newlines within a string must be escaped.
Frequently Asked Questions
A JSON validator checks if a string of text follows the strict rules of JSON (JavaScript Object Notation). It identifies syntax errors like missing quotes, trailing commas, or incorrect brackets.
When validation fails, we provide the specific error message and, when possible, the line number where the issue occurred to help you fix it quickly.
Absolutely. Validation happens entirely within your browser's memory. Your data is never sent to any server.
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