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JSON Formatter & Validator

JSON (JavaScript Object Notation) is the standard data interchange format for REST APIs and web configuration files. Unformatted JSON strings can be difficult for humans to read and debug.

What is JSON Formatter & Validator?

A JSON Formatter is a developer utility that parses unformatted or minified JSON strings, validates structural syntax, and renders human-readable indented trees.

How to Use JSON Formatter & Validator

  1. 1Paste your raw or minified JSON code into the editor.
  2. 2Click "Format / Beautify" (choose 2-space or 4-space indentation).
  3. 3Click "Minify" to strip whitespace for lightweight API payloads.
  4. 4If errors exist, the validator pinpoints exact line numbers and syntax issues.
  5. 5Use "Copy JSON" or "Download .json File".

How Does JSON Formatter & Validator Work?

Uses `JSON.parse()` for validation and `JSON.stringify(data, null, space)` for formatting.

Calculation FormulaFormatted Output = JSON.stringify(JSON.parse(input), null, indentSize)

Practical Examples

Minified to Formatted JSON

Input: `{"name":"Sunloop","type":"Tools","active":true}`

Parse and apply 2-space indentation`{ "name": "Sunloop", "type": "Tools", "active": true }`

Frequently Asked Questions

Is my confidential JSON data uploaded to a server?

No! All parsing, formatting, and validation occurs entirely inside your local browser JavaScript engine. Proprietary API keys and sensitive payloads remain safe.

Why is JSON validation failing on trailing commas?

Standard JSON specifications (RFC 8259) forbid trailing commas after the last key-value pair or array element.

What is the difference between single and double quotes in JSON?

Strict JSON specification requires double quotes (`"`) around keys and string values. Single quotes (`'`) cause syntax validation errors.

Can I convert formatted JSON back to minified single-line string?

Yes, simply click the "Minify" button to remove all indentation and newlines.

What maximum JSON file size is supported?

Browser RAM handles large JSON files up to several megabytes effortlessly.

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