JSON Formatter, Validator & Minifier
Paste raw JSON, get a clean, indented version with instant validation — or minify it down to the smallest valid string. Nothing is uploaded.
How to use the JSON formatter
- Paste your raw or minified JSON into the input box.
- Click “Format & Validate” for a readable, indented version, or “Minify” to compress it.
- If the JSON is invalid, a clear error message shows what's wrong and roughly where.
- Copy the result or download it directly as a .json file.
| Action | What it does |
|---|---|
| Format & Validate | Parses then re-stringifies with 2-space indentation |
| Minify | Parses then re-stringifies with no whitespace |
Quick answer
A JSON formatter takes raw or minified JSON and re-prints it with consistent indentation so it's readable, while validating the syntax at the same time — any missing comma, unclosed bracket, or stray character produces an immediate, specific error message rather than a silent failure. This tool does both formatting and validation in one step, entirely in your browser.
JSON Formatter — FAQs
No. Formatting, minifying, and validation all run locally using the browser's native JSON.parse and JSON.stringify — your JSON never leaves your device.
It shows the browser's own JSON parser error, which typically includes the character position of the problem (an unexpected token, a missing comma, an unclosed bracket, etc.) — the same detail you'd get from a browser's developer console.
Formatting (pretty-printing) adds indentation and line breaks to make JSON human-readable. Minifying strips all unnecessary whitespace to produce the smallest possible valid JSON string, typically used for production payloads.
No artificial limit is enforced, but very large JSON documents (tens of megabytes) may be slow to parse depending on your device, since parsing happens entirely in your browser's memory.
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