JSON Validator
Check whether JSON is valid and find the exact line and column of any syntax error.
JSON Formatter & Beautifier
Pretty-print JSON with your choice of indentation and optional key sorting. Errors are shown with line and column. Your data never leaves the browser.
How to use
- Paste JSON into the input box.
- Choose indentation and whether to sort keys.
- Click Format, then copy or download the result.
What this tool does
It parses your input with the browser’s native JSON parser, so the result follows the JSON standard exactly, and re-serialises it with consistent indentation.
Why it matters
API responses, configuration files and exported data are much easier to read and debug when they are formatted.
Frequently asked questions
Is my JSON uploaded?
No. Parsing and formatting happen in your browser, which makes the tool safe for API keys or customer data. Still, avoid pasting secrets into any website you do not trust.
Why are comments rejected?
Standard JSON does not allow comments or trailing commas. Remove them, or use a format such as JSON5 where your tools support it.
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