How to use it
- 1
Paste JSON into the input field.
- 2
Select the format action.
- 3
Copy the result or correct the reported syntax error.
What the tool can do
- Validation with the browser's standard JSON parser.
- Formatting for objects, arrays, strings, numbers, booleans, and null.
- An error message for invalid syntax.
Common use cases
- Checking an API response before debugging.
- Making a configuration file easier to review.
- Finding a missing comma, quote, or bracket.
How it works inside
Output is produced with JSON.parse and JSON.stringify.
Key order follows JavaScript parser behavior.
Questions and answers
Does it support JSON5?
No. Input must follow standard JSON syntax.
Is the JSON uploaded?
No. Validation and formatting run in the browser.