📖 What is a JSON Formatter?
A JSON formatter (also called JSON Beautifier or JSON Prettifier) takes minified or unreadable JSON text and adds proper indentation, line breaks, and spacing to make it human-readable. It also validates your JSON to check for syntax errors like missing commas, unclosed brackets, or incorrect quotes.
JSON (JavaScript Object Notation) is the most widely used data format for APIs, configuration files, and data exchange between web applications. When working with APIs, the JSON response is often minified to save bandwidth — making it impossible to read directly. A JSON formatter solves this instantly.
🔧 How to Use the JSON Formatter
- Paste your JSON text in the Input box above
- Click Format / Beautify to add proper indentation
- If your JSON has errors, the validator will show exactly what went wrong
- Click Copy to copy the formatted JSON to your clipboard
- Use Minify to compress JSON by removing all whitespace
📝 JSON Syntax Rules
- Keys must be strings in double quotes:
"name" not name
- Strings must use double quotes, not single quotes
- Arrays use square brackets:
[1, 2, 3]
- Objects use curly braces:
{"key": "value"}
- No trailing commas allowed
- No comments allowed in standard JSON
💡 Common JSON Errors and Fixes
- Unexpected token — Usually a missing comma or extra comma
- Unterminated string — A string that was opened but not closed with a quote
- Unexpected end of JSON input — Missing closing bracket
} or ]
- Duplicate keys — JSON allows duplicate keys but it is bad practice
❓ Frequently Asked Questions
Is my JSON data safe?
Yes. All formatting and validation happens entirely in your browser using JavaScript. Your JSON data is never sent to any server. It is 100% private and secure.
What is the maximum JSON size this tool can handle?
Since processing is done in your browser, the limit depends on your device's memory. It can typically handle JSON files up to several MB without issues.
What is the difference between JSON Format and JSON Minify?
Format adds indentation and line breaks to make JSON readable by humans. Minify removes all whitespace to reduce file size — useful when sending JSON over a network or storing it in a database.
Can I validate JSON arrays?
Yes. The validator supports all valid JSON structures including objects, arrays, nested objects, strings, numbers, booleans, and null values.
Does this work on mobile?
Yes. The JSON Formatter works on all devices including mobile phones and tablets without any installation.