About this tool
JSON Formatter is a browser-based tool that takes raw or broken JSON and cleans it up instantly. It validates your data, applies consistent indentation, and highlights syntax so you can read nested structures at a glance. Developers, QA testers, and anyone working with APIs or config files will find it useful for making sense of dense, unformatted output.
Reach for this tool when you paste an API response into a text editor and it comes back as one long unreadable line. It is also handy before committing config files, debugging a failed JSON parse, or minifying data to reduce payload size before sending it over a network.
How to use it
- Paste your raw or minified JSON into the input field on the left.
- Click the Format button to apply indentation and syntax highlighting.
- Review the output panel for colour-coded keys, values, and structure.
- Check the validator message to confirm your JSON is error-free.
- Click Minify to collapse the JSON into a single compact line if needed.
- Copy the formatted or minified result to your clipboard with one click.
Pro tips
- Paste JavaScript object literals first into your browser console using JSON.stringify to convert them before formatting here.
- Use the minify option before embedding JSON in environment variables or HTTP request bodies to avoid whitespace-related parsing errors.
FAQ
Why does my JSON keep failing validation?
Common culprits are trailing commas after the last item in an array or object, and single quotes instead of double quotes around keys or string values. The error highlight should point you to the exact line.
Is my data sent to a server when I format it?
No, all formatting and validation runs locally in your browser. Nothing you paste is transmitted or stored anywhere.
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