JSON Formatter
Pretty-print and validate JSON text with your chosen indentation.
- Free to use
- Accurate results
- No registration required
- Works on all devices
Paste JSON text and choose an indent size to pretty-print and validate it.
Your result
Valid
Valid JSON?
Formatted JSON{
"name": "CalcuTool",
"calculators": 500,
"active": true
}
Error (if invalid)
AI explanation
Formula
Parses the JSON text, then re-serializes it with the requested indentationWorked example
A compact JSON object
| Field | Value |
|---|---|
| JSON text | {"name":"CalcuTool","calculators":500,"active":true} |
| Indent size (spaces) | 2 |
| Valid JSON? | Valid |
| Formatted JSON | { "name": "CalcuTool", "calculators": 500, "active": true } |
Assumptions
- Uses standard JSON parsing rules — trailing commas, comments, and unquoted keys (all invalid in strict JSON) will be flagged as invalid, even though some JavaScript-like formats allow them.
- Object key order is preserved as parsed; numeric formatting follows standard JSON number serialization.
Frequently asked questions
Why does my JSON show as invalid?
Common causes: trailing commas after the last item, unquoted object keys, single quotes instead of double quotes, or a missing/extra bracket or brace — strict JSON requires double-quoted keys and strings, and no trailing commas.
Can I use this to minify JSON instead of pretty-printing it?
Set the indent size to 0 for a compact, single-line output — useful before sending JSON over the network to reduce payload size.
Does this validate against a JSON Schema?
No — it only checks that the text is syntactically valid JSON, not that it matches any particular structure or set of required fields.