Format, compress, and check JSON syntax online, preserving the original text of large integers, exponents, and numbers. Choose 2 or 4 space indentation and copy results with one click; all input is processed only in the browser.
Numeric and string literals are not converted back to floating point; up to 100 levels of nesting are allowed. Only format and syntax checks are performed, and business data is not verified.
61 / 100,000 characters
Shortcut key: Ctrl/⌘+Enter. Modifying inputs or options clears old results.
The ID is not converted to a JavaScript float first, so the original number is retained.
Not supported. This checks for standard JSON, not JSONC or JSON5; property names must use double quotes and cannot contain comments or trailing commas.
Only checks syntax and formatting, does not validate field types, required fields or business rules; up to 100 levels of nesting.
Standard JSON syntax is checked first, and whitespace is reordered according to the original lexical fragment. The output does not reserialize numbers, so large integers and exponents can be retained; business fields or JSON Schema are not verified.
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