JSON Viewer Online – Free JSON Formatter, Validator & Parser
The fastest free online JSON Viewer. Paste, format, validate and explore JSON data instantly in your browser — no account or installation required.
What is this JSON Viewer?
This is a free browser-based JSON Viewer and JSON Formatter tool. It lets you paste raw JSON text, validate whether it is correct, format it with proper indentation (pretty-print), and explore the structure in an interactive expandable tree view. It is used by developers, API testers, data analysts and anyone who needs to inspect JSON data quickly.
Key Features of this Online JSON Viewer
- Interactive JSON Tree Viewer: Explore JSON as an expandable, collapsible tree. Objects show their keys, arrays show numbered indexes. Click any node to inspect its value in the detail panel.
- JSON Formatter: Automatically pretty-prints JSON with correct indentation and line breaks, making minified JSON human-readable with one click.
- JSON Validator: Validates JSON as you type. Shows clear, friendly error messages with the exact location of any syntax error.
- JSON Parser: Parses any valid JSON string and displays its data types — strings (green), numbers (blue), booleans (purple), and null values (red) — with syntax highlighting.
- Load JSON from URL: Fetch live JSON directly from any public API endpoint or URL. Automatically handles CORS restrictions.
- Search JSON: Search any key name or value across the entire JSON structure with Next/Previous navigation.
- Copy, Paste & Minify: Quickly paste from clipboard, copy formatted JSON, or remove all whitespace to minify JSON for production use.
Use Cases for JSON Viewer and Formatter
- Debugging REST API responses by viewing the JSON structure visually
- Formatting minified JSON from production logs for human reading
- Validating JSON configuration files before deployment
- Exploring deeply nested JSON data from databases or third-party APIs
- Sharing readable, formatted JSON with team members
- Quickly checking data types and null values in API payloads
Frequently Asked Questions about JSON Viewer
What is a JSON Viewer?
A JSON Viewer is a tool that renders JSON (JavaScript Object Notation) data as a readable, interactive tree. Instead of reading flat JSON text, you expand and collapse objects and arrays, and click on nodes to inspect individual values. JSON Viewer tools are essential for developers working with APIs, configuration files and data pipelines.
How do I format JSON online?
To format JSON online using this tool: open the Text tab, paste your JSON, then click the Format button. The tool will add proper indentation and line breaks. Invalid JSON will show an error message instead.
How do I validate JSON?
Paste or type your JSON into the Text tab. The tool validates automatically as you type and shows a green tick for valid JSON or a red error message that describes the exact problem. You can also press the Load JSON button for explicit validation.
Can I load JSON from a URL?
Yes. Click Load JSON in the toolbar to open the URL dialog. Enter any public JSON API endpoint. The tool fetches the JSON and loads it into the tree viewer. It automatically retries through a CORS proxy if the server blocks direct browser requests.
What is the difference between a JSON formatter and a JSON validator?
A JSON formatter pretty-prints valid JSON with indentation. A JSON validator checks that your JSON follows correct syntax. This tool does both — it validates as you type and lets you format with one click.