JSON formatter / validator
JSON Formatter and Validator
Accepts large payloads, keeps the structure readable, and flags errors fast.
0 -> 0 bytes Valid JSON
InputAccepts JSON or JS object literals
Output
Formats live; output format toggle
Validates syntax instantly Live as you type Fits desktop & mobile
How it works
Parses JSON (or JS object literals) and re-serializes it either prettified or minified. Switch output mode to view valid JSON or a JS object literal shape.
- Pretty adds spaces and newlines; Minify strips them for compact payloads.
- Trailing commas or single quotes are rejected in JSON mode; use object literal input if needed.
Quick examples
Pretty print
{"id":1,"name":"StackAtlas","tags":["tools","json"]}
{ "id": 1, "name": "StackAtlas", "tags": [ "tools", "json" ] }
Minify
{ "ok": true, "count": 3 }
{"ok":true,"count":3}
Use object output when you need JS-ready literals for configs or snippets.
Mini FAQ
JSON vs object input?
JSON is strict; object input allows single quotes and trailing commas but still outputs valid JSON or literals.
Why is my string reordered?
Key order is preserved as parsed; arrays keep their order.
Large payload slow?
Pretty printing large data can be heavy. Minify or slice sections when working with huge files.
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