JSON Editor¶

The JSON Editor provides a powerful environment for editing, validating, and querying JSON files with support for multiple JSON formats.

Last Updated: January 2026 | Version: 1.2.1

Overview¶

FreeXmlToolkit includes a full-featured JSON Editor that supports: - Standard JSON - RFC 8259 compliant - JSONC - JSON with Comments (single-line // and block /* */) - JSON5 - Extended JSON with trailing commas, unquoted keys, and comments

Screenshot: JSON Editor with Tree View

Features¶

Text Editor¶

Feature	Description
Syntax Highlighting	Color-coded JSON for easy reading
Auto Format	Beautify JSON with proper indentation
Minify	Compress JSON by removing whitespace
Undo/Redo	Full undo/redo support
Line Numbers	Numbered lines for easy navigation
Drag & Drop	Drop JSON files directly into the editor

Tree View¶

The tree view provides a hierarchical view of your JSON structure:

Feature	Description
Interactive Navigation	Click on nodes to jump to that location in the text
Expand/Collapse	Expand or collapse nodes to focus on specific areas
Search	Search for keys or values within the tree
Sync with Editor	Synchronize selection between tree and text
Type Icons	Visual icons for objects, arrays, strings, numbers, booleans, and null

Hover Information¶

When you hover over any element in the JSON editor, you'll see: - JSONPath - The full path to the current element (e.g., $.store.book[0].title) - Type - The JSON type (object, array, string, number, boolean, null) - Key - The property key name - Value - A preview of the value (truncated for long values)

JSONPath Queries¶

Execute JSONPath queries to extract data from your JSON documents:

Query Example	Description
`$.store.book[*].author`	All authors in the store
`$..author`	All authors anywhere in the document
`$.store.book[?(@.price < 10)]`	Books cheaper than 10
`$.store.book[0,1]`	First two books
`$.store.book[-1:]`	Last book

To run a query: 1. Click the JSONPath button in the toolbar 2. Enter your JSONPath expression 3. Click Execute to see results

Validation¶

Syntax Validation¶

Click Validate to check if your JSON is syntactically correct. The editor will report: - Parse errors with line and column numbers - Detected format (JSON, JSONC, or JSON5)

JSON Schema Validation¶

Validate your JSON against a JSON Schema:

Click Schema → Load Schema...
Select your JSON Schema file
Click Schema → Validate Against Schema

The validator supports: - JSON Schema Draft 4, 6, 7 - JSON Schema 2019-09, 2020-12

Keyboard Shortcuts¶

Shortcut	Action
`Ctrl+N`	New JSON file
`Ctrl+O`	Open file
`Ctrl+S`	Save file
`Ctrl+Shift+S`	Save as
`Ctrl+Alt+F`	Format JSON
`F5`	Validate JSON
`Ctrl+Z`	Undo
`Ctrl+Y`	Redo
`Ctrl++`	Zoom in
`Ctrl+-`	Zoom out
`Ctrl+0`	Reset zoom

Supported Formats¶

JSON (Standard)¶

{
  "name": "John",
  "age": 30,
  "active": true
}

JSONC (JSON with Comments)¶

{
  // This is a single-line comment
  "name": "John",
  /* This is a
     multi-line comment */
  "age": 30
}

JSON5¶

{
  // Unquoted keys
  name: 'John',
  // Single quotes
  city: 'New York',
  // Trailing commas allowed
  items: [1, 2, 3,],
}

Button	Description
New	Create a new JSON document
Open	Open an existing JSON file
Save	Save the current document
Save As	Save with a new name
Recent	Access recently opened files
Undo/Redo	Undo or redo changes
Format	Pretty-print the JSON
Minify	Compress the JSON
Validate	Check JSON syntax
Schema	Load schema, validate against schema
JSONPath	Open the JSONPath query panel
Tree	Toggle the tree view
View	Expand all, collapse all, sync with editor
Help	Show help information

Tree View Icons¶

Icon	Type
`{ }`	Object (blue)
`[ ]`	Array (green)
`" "`	String (gray)
`#`	Number (orange)
Toggle	Boolean (cyan)
`-`	Null (gray, italic)
`//`	Comment (green, italic)

Tips and Best Practices¶

Use the Tree View for navigating large JSON documents
Enable Auto-Format after pasting JSON from external sources
Use JSONPath to quickly extract specific data
Validate against Schema to ensure data quality
Drag and Drop files for quick access

XML Editor - Edit XML files with similar features
XSLT Developer - Transform JSON to other formats

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