DevTools360 JSON Viewer is a fast JSON formatter, validator, and tree explorer built for real debugging work. Paste any JSON, instantly format it, and jump to errors with precise highlighting. The collapsible tree view makes large payloads readable, while JSONPath queries let you verify deep values in seconds.

This page is the canonical JSON viewer for DevTools360 and is updated regularly to keep formatting, validation, and performance behavior aligned with the JSON standard.

1. Paste JSON: Drop JSON into the editor or load a file or URL.
2. Auto-format: The tool formats and validates as you type.
3. Fix errors: Click the highlighted error to jump to the exact line.
4. Explore: Expand nodes in the tree view to inspect nested data.
5. Query: Use JSONPath to verify specific values or arrays.

Input JSON:

{"user":{"id":42,"name":"Ada Lovelace","roles":["admin","editor"]},"active":true,"created":"2026-01-15T10:30:00Z"}

Formatted output:

{
  "user": {
    "id": 42,
    "name": "Ada Lovelace",
    "roles": ["admin", "editor"]
  },
  "active": true,
  "created": "2026-01-15T10:30:00Z"
}

• Formatter: Pretty-print JSON with consistent indentation and spacing.
• Validator: Catch syntax errors with clear error locations.
• Minifier: Remove whitespace for smaller payloads and faster transfers.

Large or nested JSON is easier to explore with a collapsible tree view. Use JSONPath queries to pinpoint values and quickly verify data structures without manual searching.

• Trailing commas: Remove the comma before a closing } or ].
• Single quotes: JSON requires double quotes around keys and strings.
• Comments: JSON does not support comments; remove // or /* */.
• Unescaped characters: Escape newlines and quotes inside strings.
• Extra text: Ensure the document is a single JSON value, not mixed text.

• API debugging: Inspect API responses and verify payload shapes.
• Data cleanup: Fix malformed JSON before saving or importing.
• Documentation: Share formatted JSON in tickets or docs.
• Testing: Validate fixtures and sample data sets.

• JSON to YAML converter for configuration files and CI pipelines.
• JSON to CSV converter for spreadsheets and data exports.
• JWT decoder and verifier to inspect JSON payload claims.
• Regex tester to validate patterns used in JSON values.

All JSON processing happens locally in your browser. No uploads, no tracking, and it keeps working even when you are offline.

• RFC 8259 - The JSON Data Interchange Syntax
• RFC 6901 - JSON Pointer

Maintained by the DevTools360 team. Last updated: 2026-01-15. We prioritize privacy-first processing and fast performance for large JSON payloads.