JSON Viewer Online — Free JSON Formatter & Inspector | Online Gallery
Explore nested JSON, JSONL & GeoJSON payloads in browser. Inspect, validate, and navigate complex JSON, JSONL, and structured data payloads with syntax coloring.
What is JSON Viewer and what does it do?
The JSON & Data Tree Explorer provides structured syntax inspection for JSON, JSONL, and GeoJSON files in client-side memory.
- Validate JSON syntax and inspect nested object trees.
- Support for multi-line JSONL (JSON Lines) payloads.
- Copy formatted output or export files.
How does JSON Viewer work?
Parses text into JavaScript objects and formats JSON strings with 2-space indentation and syntax highlighting.
100% private: all processing happens locally in your browser using client-side WebAssembly, WebCrypto, WebAudio, and HTML5 Canvas. Your files are never uploaded to any server.
Who needs JSON Viewer?
Developers & Analysts
Inspect API payloads and log outputs without pasting sensitive tokens into online servers.
Supported file formats
JSON & Data Tree Explorer opens and processes the following file extensions directly in your browser:
.json.jsonl.geojsonHow to use JSON Viewer — step by step
- 1
Open JSON
Drop your .json or .jsonl file.
- 2
Inspect Tree
View formatted syntax or raw strings.
- 3
Copy or Save
Copy formatted output to clipboard.
Frequently asked questions
Is my JSON payload private?
Yes, 100% processed in client-side memory.
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