About this json formatter
Turn compact JSON into an indented document you can read and copy. Choose Format for two-space indentation or Minify to remove unnecessary whitespace. The validator identifies the approximate line and column of a syntax error so you can repair a missing quote, comma, or bracket. Input is parsed as data in your browser and never executed as code or uploaded to a server.
How the json formatter works
The browser JSON parser validates the input. The parsed value is serialized with two-space indentation, or no indentation in Minify mode.
JSON Formatter examples
{"name":"Ada","active":true}
{
"name": "Ada",
"active": true
}[1, 2, 3]
[1,2,3] in Minify mode
Limitations & privacy
Maximum input: 100,000 characters. JavaScript number precision applies; very large integers can lose precision. Duplicate keys retain the last value. Comments and trailing commas are not JSON. Errors identify a location, not a semantic object path.
Inputs and results stay in this browser. Only tool identifiers are stored for your recently used tools. You can clear that history from the directory.
JSON Formatter: frequently asked questions
Can I format JSON with comments?
No. Remove comments and trailing commas before formatting.
Does this reorder keys?
Object key ordering follows JavaScript serialization rules, including numeric keys.
Is pasted JSON executed?
No. JSON is parsed as data and displayed as escaped text.
Updated September 20, 2026