Free online tool
Format and validate JSON
Paste JSON to check its syntax and produce a consistently indented result. Invalid JSON is reported with a clear correction prompt.
Open the interactive JSON Formatter & Validator
The interactive tool loads in the page. Enable JavaScript to enter data, process content, and download results.
Quick guide
How to use this tool
- 01Paste JSON into the input area.
- 02Format or validate the content.
- 03Review and copy the formatted output.
Capabilities
Features and supported formats
- Parses and validates JSON syntax.
- Formats valid JSON with readable indentation.
- Keeps the submitted content in the browser.
Supported formats
Input and output: JSON text.
Answers
Frequently asked questions
Why is my JSON rejected?
JSON requires quoted property names and strings, commas between items, and matching brackets. Check the error area and inspect the surrounding syntax.
Does formatting change the data?
Formatting changes whitespace and indentation. The parsed JSON values remain the same when input is valid.