JSON Formatter
Format and beautify messy JSON online — 2 spaces, 4 spaces or tabs, with instant validation and precise error locations. 100% in your browser.
Line 1, column 1: Unexpected end of input
This tool runs entirely in your browser. Your data never leaves your device — it is not uploaded to any server.
How to use
- 1Paste your JSON into the input box.
- 2Pick an indentation: 2 spaces, 4 spaces or a tab.
- 3Copy the beautified result — or fix the reported line and column if the JSON is invalid.
JSON Formatter
Paste minified or badly indented JSON and get clean, readable output immediately. Choose 2 spaces, 4 spaces or tab indentation, and the result updates live as you type or edit — perfect for inspecting API responses, config files and log payloads.
Invalid JSON is not a dead end: the formatter pinpoints the exact line and column of the syntax error, so a missing comma or bracket takes seconds to find instead of minutes.
Frequently asked questions
Is there a size limit for the JSON I can format?
There is no hard limit — formatting happens locally in your browser. Very large files (tens of MB) may feel slow because the result recalculates as you type, so paste them in one go and edit carefully.
Does formatting change my data?
No. The values, key order and structure stay exactly the same; only whitespace and line breaks are added. The output is byte-for-byte equivalent JSON.
Is my JSON uploaded to a server?
No. Everything runs locally in your browser with JavaScript — your data never leaves your device.
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Embed this tool
Put this tool on your own site with one line — it runs entirely in the visitor's browser.
<iframe src="https://zoyku.com/en/tools/json-formatter?embed=1" width="100%" height="640" style="border:0;border-radius:16px" title="Zoyku — json-formatter" loading="lazy"></iframe>