RFC 8259 JSON Beautifier, Minifier & Tree Inspector

JSON Formatter

Beautify, format, validate, and minify JSON data with strict RFC 8259 compliance, root primitive support, duplicate key warnings, interactive tree inspection, and UTF-8 byte calculations.

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Format valid JSON to inspect interactive DOM tree.
JSON Structure Valid: No syntax errors detected.
RFC 8259 Valid
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RFC 8259 JSON Standards & Developer Specification Reference
Strict RFC 8259 Rules

Strict JSON requires double-quoted strings ("key": "value"), prohibits trailing commas, forbids single/multi-line comments (//), and rejects unquoted keys.

Duplicate Key Detection

Standard JSON parsers may overwrite duplicate object keys. Our engine audits JSON structures for repeated key names and displays warnings with path locations.

Prototype Pollution Protection

Prevents Prototype Pollution (__proto__, constructor, prototype keys) during tree rendering, preventing modification of application prototypes.

Root Primitives & UTF-8 Bytes

Supports root primitives ("Hello", 123, true, null) and accurately computes UTF-8 byte sizes for international Unicode data.