A free JSON formatter and validator that runs entirely in your browser. Paste minified or messy JSON to pretty-print it and validate syntax. Copy formatted or minified output with one click. No data is sent to any server.
Why Use This JSON Formatter?
- Validate: Get immediate feedback when JSON is invalid, with a clear error message.
- Readable: Formatted output is indented for easy reading.
- Copy options: Copy the formatted (indented) or minified (single-line) version.
- Private: All processing happens locally in your browser.
Key Features
- Format & validate: One click parses and reformats JSON; invalid input shows an error in the output area.
- Copy formatted or minified: Buttons to copy the pretty-printed or compressed JSON.
How it Works
The tool uses the native JSON.parse() to validate and parse the input. Formatted output is produced with JSON.stringify(data, null, 2). No external libraries are used.
Try the JSON Formatter
Paste your JSON into the input box and click Format / Validate. Use the copy buttons to get formatted or minified JSON. Everything runs in your browser.
简体中文
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한국어
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日本語
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