Does the formatter fix invalid JSON?
No. It reports a parse error so you can correct the source instead of silently changing data.
JSON Formatter
Validate and format JSON locally as readable or compact output.
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Parse, then serialize
The tool uses JSON.parse to validate the complete input and JSON.stringify to serialize the parsed value with the selected indentation. Invalid input returns an error and no partial formatted result.
formatted = JSON.stringify(JSON.parse(input), null, indentation)Worked example
Readable formatting
Inputs: input: {"tool":"ToolGlo","active":true} · indentation: 2 spaces
Illustrative result: A two-space-indented JSON object
The parsed object is serialized with line breaks and two spaces before nested properties; the underlying values are unchanged.
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Frequently asked questions
Is my JSON sent to a server?
No. Validation and formatting run in the client-side browser component.