How to use JSON Formatter & Validator
- Paste a JSON value, object, or array.
- Choose pretty formatting or compact minification.
- Process the text. Fix any reported syntax error, then copy or download valid JSON.
A closer look
Check JSON syntax and choose readable indentation or compact output. Valid JSON requires double-quoted property names and strings; comments and trailing commas are not accepted. The formatter parses with JavaScript’s JSON parser and serializes the result. It validates syntax, not a schema or your application’s business rules.
A practical example
Format {"name":"Sam","active":true} into readable indented JSON, or choose Minify for a compact version. Property names need double quotes.
A useful tip
JavaScript numbers cannot exactly represent all integers above 9,007,199,254,740,991. Store large identifiers as strings. Duplicate object keys keep only their last value when parsed.
Good questions. Simple answers.
Does valid JSON mean my API will accept it?
No. An API may require specific fields, types, or values. This tool checks JSON syntax only.
Can formatting change the data?
Duplicate keys collapse to the last value and large numeric values may lose precision under JavaScript number rules. Avoid those inputs when exact preservation is required.
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