JSON formatter & validator
Format, minify and validate JSON instantly — with a collapsible tree view and exact error locations. Runs entirely in your browser, so your data never leaves your device.
Formatted output and tree view appear here.
How it works
Paste your JSON
Drop in raw, minified, or messy JSON from an API response, config file, or log.
Format & validate
Beautify or minify with one click. Invalid JSON is flagged with the exact line and column.
Explore & export
Browse the collapsible tree, then copy or download the clean result.
What is JSON formatting?
JSON(JavaScript Object Notation) is the most common format for APIs and configuration, but real-world JSON is often minified into a single line or littered with inconsistent spacing. A formatter re-indents it into a clean, readable structure; a validator confirms it's syntactically correct before you ship it.
This tool does both, plus a collapsible tree view for exploring nested data. Because it runs 100% in your browser, nothing is uploaded — making it safe for tokens, payloads, and other sensitive data that you'd never want to paste into a server-side tool.
Frequently asked questions
Is this JSON formatter free and private?+
Yes. It's completely free with no sign-up, and it runs entirely in your browser — your JSON never leaves your device or touches a server, so it's safe for sensitive data.
What's the difference between format and minify?+
Formatting (beautifying) adds indentation and line breaks so JSON is easy to read. Minifying strips all whitespace to produce the smallest possible payload — ideal for production responses and config.
How does the validator report errors?+
It parses your JSON and, when something is wrong, shows the exact error message along with the line and column where parsing failed, so you can jump straight to the problem.
What is the tree view for?+
The tree view renders your JSON as a collapsible hierarchy, making it easy to explore deeply nested objects and arrays without scanning raw text. Click any node to expand or collapse it.
Is there a size limit?+
There's no hard limit, but because everything runs in your browser, extremely large files (tens of MB) may be slow to render. For typical API responses and config files it's instant.
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