JSON Formatter
Pretty Print & Minify
Validate strict JSON, pretty-print it with adjustable indentation, or minify it into compact output using the browser JSON parser.
What is this tool?
This JSON formatter validates, pretty-prints, and minifies strict JSON. It uses the browser's JSON parser, so it follows the same rules as JSON.parse: double-quoted strings and property names, no comments, no trailing commas, and valid number syntax.
Pretty-printing adds line breaks and indentation so nested objects and arrays become readable in reviews, logs, documentation, and fixtures. Minification removes insignificant whitespace for compact transport or embedding.
Use it to inspect API responses, clean config snippets, prepare examples, or confirm that a copied payload is valid JSON before handing it to another system.
How to use
- Use Prettify to turn compact JSON into indented output.
- Set the indentation width from 1 to 8 spaces.
- Use Minify to remove unnecessary whitespace from valid JSON.
- Fix parser errors before copying the output; comments, trailing commas, and unquoted keys are not valid strict JSON.
Examples
| Input / setting | Output | Notes |
|---|---|---|
prettify {"id":1,"name":"Ada"} | {\n "id": 1,\n "name": "Ada"\n} | Two-space formatted JSON output. |
minify {\n "id": 1\n} | {"id":1} | Whitespace removed from valid JSON. |
{id:1} | SyntaxError | Strict JSON requires quoted property names. |
Related tools & concepts
Last reviewed: 2026-05-08