JSON Formatter & Validator
Turn compact JSON into readable, indented data and catch syntax errors before using it in an application. Choose two spaces, four spaces or compact output.
- Validate JSON syntax while formatting
- Choose 2-space, 4-space or compact output
- Copy formatted objects and arrays
Inspect nested data
Paste a JSON object or array, choose indentation and format it. Line breaks make nested structures easier to inspect without changing their parsed values.
Compact an API sample
Select compact output to remove formatting whitespace. Spaces inside string values remain part of the data.
Fix invalid JSON
JSON requires double-quoted property names and forbids comments and trailing commas. Correct the reported syntax problem before formatting again.
Understand parsing limits
The formatter uses JavaScript JSON parsing. Duplicate object keys keep the last value, and large numeric values may lose integer precision; quote identifiers that must remain exact.
JSON Formatter FAQs
No. It checks JSON syntax, not required fields, business rules or JSON Schema constraints.
Not directly. Convert single quotes, comments and unquoted keys into valid JSON first.
For ordinary valid JSON, indentation changes whitespace outside strings rather than the parsed data. However, this formatter parses and serializes with JavaScript: duplicate keys keep the last value and large unquoted integers may lose precision. Preserve an original response when exact bytes matter.