JSON Formatter
Format, minify, and validate JSON data with instant error detection. Essential tool for developers working with APIs, configuration files, and data interchange.
How to Use This Calculator
- Paste your JSON data into the input area.
- Choose an action: Format (pretty-print), Minify (compress), or Validate (check syntax).
- Review the output or error message for any issues.
- Click "Copy Output to Clipboard" to use the result elsewhere.
Formula
Invalid JSON will fail to parse with a descriptive error message indicating the exact location and type of the syntax error.
Examples
{“status”:“ok”,“data”:{“users”:42}} → Formatted with nested indentation for readability.
Reduces a 50KB formatted JSON to ~35KB for faster network transmission. Ideal for API responses and config files.
{“name”: “John”, age: 30} — Missing quotes on age will produce a parse error with exact location.
Frequently Asked Questions
What is JSON?
JSON (JavaScript Object Notation) is a lightweight, text-based data interchange format. It is language-independent but uses conventions familiar to programmers of C, JavaScript, and Python.
Why are my quotes not working?
JSON requires double quotes for property names and string values. Single quotes (‘key’) are not valid JSON. Also, trailing commas are not allowed.
What does “minified” mean?
Minified JSON has all unnecessary whitespace removed, producing the smallest possible output. It’s harder for humans to read but more efficient for data transfer and storage.
Is my data sent to a server?
No. All parsing and formatting happens locally in your browser. Your data never leaves your device.