Free JSON Formatter & Validator
Beautify, minify, and validate your JSON data. All processing happens locally in your browser, ensuring your data stays private and secure.
- Free
- No signup
- Files stay on your device
How to use the JSON Formatter & Validator
Minified or hand-edited JSON is hard to read and easy to break with a single stray comma. This tool instantly formats messy JSON into clean, indented code and validates it, pinpointing syntax errors — all locally in your browser, so sensitive data never leaves your device.
- 1Paste your JSON into the editor.
- 2The tool formats it and checks for syntax errors.
- 3Jump to any error the validator highlights and fix it.
- 4Copy the clean, formatted JSON when you’re done.
Frequently asked questions
What does this JSON tool do?
It formats and beautifies messy or minified JSON into clean, indented, readable code, and validates it — pointing out syntax errors so you can fix broken JSON quickly.
Is my JSON data private?
Yes. All formatting and validation happen locally in your browser. Your JSON is never uploaded to a server, so it is safe to use with sensitive data.
Why is my JSON invalid?
The most common causes are trailing commas, single instead of double quotes, missing brackets or braces, and unescaped characters. The validator highlights where the parser fails so you can pinpoint the problem.
What is the difference between formatting and minifying JSON?
Formatting adds indentation and line breaks so people can read the data; minifying strips all of that whitespace to make the payload as small as possible. The data is identical either way.
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