JSON Formatter & Validator

Format messy JSON with 2 or 4-space indentation, validate it with precise error positions, and minify it back to a compact string. Handles large documents instantly, all locally.

100% free No uploads Runs in your browser No signup

JSON formatter

Input

0 characters

Result

—

Validation is strict: the parser reports the exact position of syntax errors. The indent setting applies to beautified output; minify strips every unnecessary byte for production use.

How to use the JSON Formatter & Validator

1
Open the tool above — it is already running, no install or account needed.
2
Enter your input and adjust the options to match what you need.
3
Copy or download the result — everything was processed locally in your browser.

Private by design

This tool runs 100% inside your own browser using local JavaScript — your input never touches a server. That makes it instant, offline-capable in many cases, and private even for sensitive data.

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