MetaForge Tools

JSON Formatter & Viewer

Paste JSON or JSON-like text and get an automatically formatted, collapsible tree view. Supports single quotes, True/False compatibility, top-level numbers, and one-click copy.

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Paste JSON to format and view it here.

Top-level numbers, strings, booleans, and null are valid JSON and are supported.

Output result

Formatted output will appear here automatically.

JSON format reference

Format strict JSON and normalize common JSON-like input

Standard JSON uses double quotes, lowercase true and false values, and null. This formatter first tries strict JSON, then a compatibility parser for common JavaScript- and Python-style input. Every successful result is serialized as standard JSON with four-space indentation.

Accepted input and output

  • Strict JSON objects, arrays, strings, numbers, Booleans, and null values.
  • Single-quoted strings, unquoted object keys, comments, and trailing commas accepted by JSON5.
  • Python-style True, False, and None values normalized to true, false, and null.
  • Collapsible object and array branches, plus one-click copying of the formatted result.

Compatibility example

Input

{'active': True, 'deletedAt': None, 'count': 3}

Standard JSON output

{
    "active": true,
    "deletedAt": null,
    "count": 3
}

Frequently asked questions

Is JSON with single quotes valid JSON?

No. RFC 8259 requires double-quoted strings and property names. MetaForge accepts many single-quoted JSON-like inputs for convenience, then outputs strict JSON with double quotes.

Can a number, string, Boolean, or null be the top-level JSON value?

Yes. A JSON text can contain any serialized JSON value, so values such as 42, true, null, and a quoted string are supported.

What happens when the input contains an error?

The formatter reports the parser message and the line and column when available. If a complete valid JSON value appears before trailing invalid content, that valid segment is still shown.

Does MetaForge upload the JSON I paste?

No. Parsing, normalization, formatting, folding, and copying run locally in your browser.