JSON Formatter & Validator
Beautify, minify and validate JSON with clear error messages showing the exact line and column.
Result
How to use
- 1
Paste your JSON into the box.
- 2
Choose Beautify or Minify and the indent size.
- 3
If the JSON is invalid, the exact line and column of the problem is shown — otherwise copy the result.
Questions
Is my JSON sent to a server?
No. Formatting and validation happen entirely in your browser, so it is safe for API responses and config files.
Why is my JSON invalid?
The most common causes are single quotes instead of double quotes, a trailing comma after the last item, unquoted property names and comments — none of these are allowed in standard JSON.
Why did a very large number change?
JavaScript stores numbers as 64-bit floating point, so integers above 9,007,199,254,740,991 (2⁵³ − 1) can lose precision. Keep such IDs as strings.
About this JSON Formatter tool
JSON Formatter & Validator — Beautify, minify and validate JSON with clear error messages showing the exact line and column. It is one of 200 free tools on namasivayam.in, made by software engineer Namasivayam Vadivelan for everyday use in India.
Everything is calculated instantly in your browser: nothing you type or upload is sent to any server, there is no sign-up, and it works on mobile and desktop. Paste your JSON into the box.
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Results are estimates to help you plan. They are not financial, tax or medical advice.