Developer Tools

JSON Formatter

Format, validate, and minify JSON data with syntax highlighting

Input JSON
6 lines·91 chars
Output

Output will appear here

Paste your JSON and click format

Client-side processing

Your data never leaves your device

JSON Formatter & Validator

Paste minified or broken JSON and get it instantly formatted, indented, and validated. Highlights syntax errors with the exact line number — the fastest way to debug API responses.

FAQ

How do I format JSON online?

Paste your JSON and click Format. The tool indents it with 2-space or 4-space tabs and validates the structure.

How do I fix invalid JSON?

The validator highlights the error line. Common issues: trailing commas, missing quotes on keys, unescaped characters.

What is the difference between JSON and JSONC?

JSONC allows // comments. Standard JSON does not. Strip comments before parsing with most parsers.

How do I minify JSON?

Use the Minify button to remove all whitespace from JSON — useful when sending data in HTTP requests to reduce payload size.

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