Free Online JSON Formatter & Validator

Format, beautify, validate, and minify JSON payloads with syntax highlighting, error diagnostics, and tree inspection.

Client-Side Guarantee: Your JSON payloads are parsed and formatted entirely on your device. Zero data transmission.

How to Use the JSON Formatter & Validator

  1. Paste your raw or minified JSON into the editor.
  2. Click 'Format / Beautify' to indent and organize the structure.
  3. If there is a syntax error, review the error banner for the exact line and issue.
  4. Use 'Minify' to strip all whitespace for production transmission.
  5. Click 'Copy' or 'Download' to use your clean JSON.

Key Features

✓ Beautify JSON with configurable 2-space or 4-space indentation
✓ One-click JSON minifier to compress payloads for production
✓ Precise syntax error detection with error message and position locator
✓ Interactive expandable tree viewer for deep inspection
✓ Copy formatted JSON or download as a `.json` file
✓ 100% client-side: safe for sensitive API tokens and user payloads

About JSON Formatter & Validator

Format messy, unindented JSON payloads into clean, readable structures. Spot syntax anomalies like missing commas or mismatched brackets with precise error feedback and interactive tree view.

Frequently Asked Questions

Is it safe to format JSON containing API payloads or secrets?

Yes. Processing runs entirely in your local browser JavaScript engine. No JSON data is ever transmitted across the internet.

What is the maximum JSON payload size supported?

The tool can process multi-megabyte JSON files smoothly, limited only by your browser's available memory.

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