Online JSON Formatters

Format, validate, and beautify your JSON data with these powerful online tools.

JSON Formatter & Validator from CuriousConcept

JSON formatter and validator from CuriousConcept provides a simple yet feature-complete interface to validate and format JSON input according to one of the RFC 8259, RFC 7159, RFC 4627, or ECMA-404 specifications.

How to Use

To validate and format your JSON:

  1. Paste your text or URL into the JSON Data/URL edit box
  2. Choose a specification you want to validate against in "JSON specification" field
  3. Choose the number of spaces you want to use for tabulation in "JSON Template" field
  4. Click "Process" button

Features

  • Formatted Output: See your JSON formatted according to the selected specification
  • Collapsible Structure: Nesting structure will be collapsible for better readability
  • Copy to Clipboard: Easily copy the formatted JSON
  • Download as File: Save formatted JSON to your Downloads folder
  • Query JSON: Execute JSONPath expressions
  • Format Conversion: Convert JSON to PHP, XML, or YAML
  • Error Validation: See all validation errors listed with locations

If your JSON has validation errors, you will see all of them listed in the "Validator Output" box. When you click on an error, you will see its location in the formatted JSON output field.

JSON Formatter from JSONFormatter.org

JSON Formatter from jsonformatter.org is a multi-purpose tool which allows JSON validation, formatting, beautification, minification, and conversion.

Main Functions

To use this formatter, insert your unformatted JSON to the edit box on the left, then click one of these buttons:

  • Validate: Check if your JSON is valid
  • Format/Beautify: Make JSON human-readable with proper indentation
  • Minify/Compact: Remove all whitespace to reduce file size
  • Convert JSON to: Transform to other formats

View Modes

You will see resulting JSON in the edit box to the right. Click on the "Text" button in the top menu to change how JSON is displayed:

  • Code view: Syntax-highlighted code
  • Form view: Edit as a form
  • Text view: Plain text
  • Tree view: Hierarchical structure
  • Preview: Visual representation

You can also query, transform or sort JSON by clicking on the filter icon in the toolbar.

Additional Features

JSON Graph Visualization

Some formatters offer graph visualization where you can:

  • Zoom in and out
  • Expand and collapse nodes
  • See relationships between data
  • Export visualizations

Batch Processing

Advanced formatters support:

  • Processing multiple JSON files at once
  • Applying the same transformations to all files
  • Batch validation

Schema Validation

Many formatters can validate your JSON against a JSON Schema to ensure:

  • Data conforms to expected structure
  • Required fields are present
  • Data types are correct
  • Values meet constraints

Best Practices

When formatting JSON, keep these tips in mind:

  • Consistent Indentation: Use 2 or 4 spaces (not tabs) for better compatibility
  • Validate First: Always validate before formatting to catch errors
  • Minify for Production: Use minified JSON in production to reduce bandwidth
  • Beautify for Development: Use formatted JSON during development for readability
  • Version Control: Use formatted JSON in version control for better diffs