JSON Formatter
Format, validate and minify JSON online. Pretty-print with 2 or 4 spaces, get precise error positions, and copy or download the result. Nothing leaves your browser.
How to use
- Paste your JSON into the input area.
- Click Format to pretty-print — in the tree view, click any object or array to collapse or expand it, or use "Expand all" / "Collapse all".
- Switch to the Raw tab for plain text, then copy or download the result.
What is JSON Formatter?
JSON (JavaScript Object Notation) is the standard data format for APIs and configuration files. This tool pretty-prints compact JSON with your choice of indentation, validates the syntax and pinpoints the exact line and column of any error, and minifies JSON back to a single line.
Parsing runs entirely in your browser, so private API responses and configuration files are never sent anywhere.
Frequently asked questions
Is my JSON uploaded anywhere?
No. Parsing and formatting happen entirely in your browser with JavaScript — nothing is transmitted to any server.
Why does my JSON fail validation?
The most common causes are trailing commas, single quotes instead of double quotes, unquoted keys, and unescaped newlines inside strings. The error message points to the exact position.
Does formatting change my data?
No. Formatting and minifying only change whitespace. Numbers, strings and structure stay exactly the same, so the formatted output is byte-for-byte equivalent data.
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