HomeJSON Formatter & Compressor

JSON Formatter & Compressor

Professional online JSON parser, formatter, validator, and minifier

Formatted Result

How to Use

Simple Steps:

  1. Paste your JSON string into the input box on the left.
  2. Click 'Format' to beautify the structure, or 'Minify' to remove whitespace.
  3. If the JSON has syntax errors, try clicking the 'Auto Fix' button.
  4. Click the 'Copy' button in the top right of the result area to copy to clipboard.

Escape Output Example

When 'Escape Output' is enabled, the result becomes a stringified JSON, suitable for embedding in code.

Normal Output

{ "message": "Hello \"World\"", "newline": "Line 1\nLine 2" }

Escaped Output

{\n \"message\": \"Hello \\\"World\\\"\",\n \"newline\": \"Line 1\\nLine 2\"\n}

Key Features

  • Syntax Highlighting: Different colors for different data types.
  • Error Detection: Real-time validation of input JSON syntax.
  • Auto Fix: Attempts to fix common JSON errors (e.g., single quotes, trailing commas).
  • Minification: Removes all unnecessary whitespace to reduce size.
  • Escaping/Unescaping: Convenient for use in Java/JS strings.
  • Dark Mode: Eye-friendly color scheme.

What is JSON?

JSON (JavaScript Object Notation) is a lightweight data-interchange format. It is based on a subset of the JavaScript Programming Language. JSON is easy for humans to read and write, and it is easy for machines to parse and generate.

JSON Syntax Rules

  • Data is in name/value pairs
  • Data is separated by commas
  • Curly braces hold objects
  • Square brackets hold arrays
  • Keys must be wrapped in double quotes

JSON Data Types

TypeDescriptionExample
StringA sequence of Unicode characters wrapped in double quotes"Hello World"
NumberInteger or floating point42, 3.14
ObjectUnordered set of key/value pairs{"name": "John"}
ArrayOrdered list of values[1, 2, 3]
Booleantrue or falsetrue
nullEmpty valuenull

Common Issues

Why is my JSON always erroring?

The most common reasons are keys not being in double quotes (allowed in JS objects, but not JSON) or trailing commas.

Can I use single quotes?

No. The standard JSON specification mandates double quotes.

More info: JSON.org | RFC 8259 | Wikipedia: JSON

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