JSON Formatter and Validator Online
Format JSON, validate JSON syntax, or minify JSON online.
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Format JSON, validate JSON, and minify JSON online
JSON formatting turns compact JSON into readable indentation. JSON validation checks whether the syntax is valid. This is useful for API responses, configuration files, front-end test data, and backend debugging.
Common needs include json formatter, json validator, json checker, and json minifier. Most errors come from quotes, commas, brackets, or invalid values.
Formula or logic
- JSON objects use { }
- JSON arrays use [ ]
- Keys and strings must use double quotes
- Trailing commas are not valid in JSON
- Formatting changes whitespace, not the data values
Example
If an API returns compressed JSON, paste it into the tool to format it and inspect the field structure. If the syntax is invalid, validation will fail.
Common questions
Can JSON use single quotes?
No. Standard JSON requires double quotes for keys and strings.
Does formatting change JSON data?
Normal formatting changes indentation and whitespace, not the data values.
Why does JSON validation fail?
Common causes include trailing commas, missing commas, unmatched brackets, and unquoted keys.