JSON Validator

What is the JSON Validator?

Validate JSON and see the exact parse error if it is invalid. Validating JSON shows exactly where syntax errors occur, saving time when APIs or configuration files fail.

How to use the JSON Validator

1. Paste or type your your text into the box (a sample is pre-filled so you can see how it works).
2. Results update automatically as you type; you can also press Calculate.
3. Read the output: result.
4. Use the 📊 chart to see the result visually, then copy or share it.

Where the JSON Validator helps in real life

Your app crashes on startup after someone edited its configuration file. The validator points to a missing comma on line 18, which explains the failure in seconds.

A developer checks a hand-written request body before sending it to an API that returns unhelpful error messages.

Common mistakes to avoid

• Using single quotes around keys or strings.
• Leaving a trailing comma after the last item.
• Adding // comments, which standard JSON rejects.
• Forgetting to escape double quotes inside string values.

💡 Practical tip: The first reported error is usually the cause of later errors, so fix it first.

Tips for better results

• Fix the first error first.
• Use a formatter for readability.
• Validate after edits.

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