Chartixo
Developer Tools

JSON Formatter & Validator

Format, validate, beautify, and minify JSON data with exact syntax error line and column detection.

Indent:
Valid JSON syntax
Runs 100% locally in your browser. Zero data transmission.

How It Works & Underlying Concept

JSON (JavaScript Object Notation) is an open standard file format and data interchange format that uses human-readable text to store and transmit data objects. Validating and formatting JSON makes complex API payloads readable and helps engineers diagnose malformed syntax like missing commas, trailing commas, or unmatched brackets.

Mathematical Formula / RuleParsed via JSON.parse() and formatted via JSON.stringify(obj, null, indent) with parse position inspection.
Quick Instructions
1Paste your raw or minified JSON into the editor.
2Select your preferred indentation (2 spaces, 4 spaces, or Tabs).
3Click 'Format JSON' to beautify, or 'Minify' to compress.
4If there is a syntax error, review the error message showing the line and column number.

Key Capabilities

  • Format JSON with 2-space, 4-space, or Tab indentation
  • Instant Minify/Compress button for production payloads
  • Exact syntax error detection with line and column highlighting
  • Inspect payload statistics: byte size, key count, and nesting depth
  • 100% private: no data sent to any remote server
Real-World Example

API Payload Debugging

A developer receives an error from an external API: 'Unexpected token } in JSON at position 42'.

Step 1:Paste the raw JSON payload into Chartixo's JSON Formatter.
Step 2:The validator highlights line 4, column 12 indicating a forbidden trailing comma after the last property.
Step 3:Remove the comma and re-format.
Result: The JSON is valid and neatly indented with full property stats.
Technical Notes & Limits
  • Standard JSON does not permit comments or single-quoted strings (as per RFC 8259).

Frequently Asked Questions

Can JSON contain comments?▾
Standard JSON does not support comments. Including // or /* */ will cause standard JSON parsers to report a syntax error.
Why does my JSON have an error on a trailing comma?▾
Unlike JavaScript objects, standard JSON specifications strictly prohibit trailing commas after the final element in arrays or objects.
Is my confidential API data safe here?▾
Yes, completely. Formatting and validation occur 100% in your local browser runtime. No data is transmitted across the internet.

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