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JSON Formatter and Validator
Validate, pretty-print and minify JSON locally with clear syntax errors.
How to use this tool
Paste JSON, then choose Format for indentation or Minify for compact output. Invalid JSON shows a syntax error and clears the previous result.
What to know
This tool uses the standard JavaScript JSON parser. Comments and trailing commas are invalid. Large integers beyond JavaScript precision may change; keep exact identifiers as quoted strings. Duplicate keys keep their last value.
Inputs stay on your device. Explore the full utility directory for more free tools.
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