JSON is the language of the modern web — APIs return it, configuration files are written in it, and SEO structured data is built on it. But raw JSON is a wall of text that is painful to read. Our free JSON Viewer makes it explorable: paste any JSON, hit Format & Validate, and get clean indented output plus a collapsible tree where every object and array expands with a click. No signup — just paste and go.
Everything runs in your browser, so your data is never uploaded anywhere — safe for private payloads and API keys. If the JSON is broken, you get the exact error message with the character position and surrounding text, pointing you at the missing comma or stray quote. Copy the result back out formatted for humans or minified for production.
Bookmark it — whether you are validating a webhook payload at midnight or teaching a colleague what valid JSON looks like, a fast, private formatter you never install is a tool you will use every week.
JSON Viewer
Format, validate and pretty-print JSON with collapsible tree view.
How to use
- Paste or type your JSON into the text box.
- Click Format & Validate.
- If there is an error, read the message and character position, fix the JSON, and validate again.
- Click the arrows in the tree to expand or collapse nested objects and arrays.
- Use Copy Formatted for readable output or Copy Minified for compact production-ready JSON.
FAQs
Is my JSON sent to any server?
No. The viewer runs entirely in your browser with JavaScript — your data never leaves your computer, so it is safe to inspect private API responses and configuration files.
How do I find where a JSON error is?
The error message includes the exact character position plus a snippet of the surrounding text. Jump to that position in your editor, fix the issue, and paste the JSON back into the viewer to re-check.
Formatted vs minified — which should I copy?
Copy Formatted when humans need to read it (documentation, debugging). Copy Minified when machines consume it (API payloads, production files) — minified JSON has all unnecessary whitespace removed.