JSON Formatter

Formats, minifies and validates JSON. Paste a blob — one long line from an API, a config that will not parse — and get it pretty-printed with consistent indentation, or compacted for transport, with syntax errors reported instead of silently tolerated.

How to use

1. Paste the JSON.
2. Format to read it, minify to ship it.
3. If parsing fails, read the error and fix the syntax at the reported spot.
4. Copy the result back to wherever it lives.

When you actually need this

• Making an API response readable enough to find the field you are after.
• Locating the syntax error in a config file that stopped parsing.
• Minifying a payload before embedding it in a request or environment variable.
• Normalising formatting before diffing two JSON documents.

The four errors that cause most invalid JSON

JSON is stricter than JavaScript, and almost every parse failure is one of four things: trailing commas after the last item (legal in JS, fatal in JSON), single quotes instead of double, unquoted keys, or comments — JSON has none. The validator here points at the position where parsing broke, which is usually at or just after the offending character. Formatting only changes whitespace: key order and values stay untouched, so a formatted file is semantically identical. Minifying strips the whitespace back out — typically a meaningful saving on large payloads, and reversible at any time by formatting again.

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FAQ

Does JSON Formatter send my input to a server?

No. The conversion runs in JavaScript inside the page, so API keys, tokens, config files and any other sensitive text stay on your machine. You can verify this by opening your browser's network tab while you use the tool.

Does JSON Formatter handle Unicode and non-ASCII characters?

Yes. Text is processed as UTF-8, so accented Latin, Korean, Japanese, Chinese, Cyrillic, Arabic and emoji all round-trip correctly rather than turning into question marks.

Can I use the output in production code?

Yes — the output follows the relevant standard exactly and is safe to paste into your project. As with any tool, run your own tests before shipping anything that depends on it.