JSON formatter, minifier & validator
Clean up messy JSON or shrink it for production, all without leaving your browser. This free tool beautifies, minifies, and validates JSON instantly with clear, human-readable error messages when something breaks — nothing you paste is ever uploaded to a server, and there’s no signup or watermark required.
How to use it
- Paste or type your JSON into the input box.
- Click Beautify for readable, indented JSON or Minify to strip all whitespace.
- Click Validate to quickly check if your JSON is well-formed.
- Copy the result with one click — your original input is never sent anywhere.
FAQ
- Is my JSON uploaded to a server?
- No. Parsing and formatting happen entirely in your browser using built-in JavaScript — your data never leaves your device.
- What happens if my JSON is invalid?
- The tool shows a clear error message including the exact parser error, so you can quickly spot and fix the problem, such as a missing comma or unclosed bracket.
- Can I minify JSON to make it smaller for production?
- Yes — click Minify to remove all unnecessary whitespace and produce the smallest valid representation of your JSON.
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