JSON Validator & Formatter
Paste or type JSON to instantly validate and pretty-print it. Syntax errors are shown with their exact line and column so you can fix them quickly.
How to use
Type or paste any JSON into the left textarea. The validator runs automatically (debounced 250 ms) and shows a green Valid JSON banner — including key count, depth, and character stats — or a red error banner with the exact position of the syntax mistake. The right textarea shows the formatted output, which you can copy or push back as input.
Common JSON errors
- Trailing commas after the last array or object value.
- Single-quoted strings instead of double-quoted.
- Unescaped control characters inside strings.
- Missing colon between object key and value.