Free Developer Tool
Format messy JSON data into a readable structure and instantly validate it for syntax errors.
Input JSON
Formatted output
Formatted output will appear here…How It Works
Or click "Load sample" to see the tool in action
Errors show with a description as you type
Choose indent size or compress to one line
Paste directly into your code or API request
FAQ
JSON (JavaScript Object Notation) is a lightweight data format used to exchange data between servers and web applications. It is human-readable, language-independent, and supported natively in every modern programming language.
Formatting (pretty-printing) adds whitespace and indentation to make JSON easy to read. Minifying removes all unnecessary whitespace to reduce file size — useful when sending data over a network or storing it efficiently.
Common causes include trailing commas after the last item in an array or object, single quotes instead of double quotes around keys or values, unescaped special characters in strings, and missing or mismatched brackets.
Yes. All processing happens entirely in your browser. No data is sent to any server. You can verify this by checking your network tab — no requests are made when you format or validate JSON.