Free JSON Formatter & Validator
Format, indent, validate, and minify JSON strings in real time. Pinpoint syntax errors instantly and beautify unformatted API responses.
How to Format & Validate JSON Online
Paste JSON
Paste messy or unformatted JSON code into the editor workspace.
Format or Minify
Click Format to indent cleanly or Minify to strip whitespace for compact payloads.
Copy or Download
Copy your valid JSON back to your code editor or save it as a .json file.
100% Confidential
JSON payloads and API keys are parsed strictly in your browser. No data is ever sent over the network.
Line Error Detection
Pinpoint syntax errors, missing commas, or unescaped quotes with exact line and position indicators.
Instant Minification
Compress JSON structures to the smallest possible byte size for production API optimization.
Developer Friendly
Configurable indentation spaces, one-click clipboard copying, and keyboard shortcuts support.
Frequently Asked Questions
Common JSON errors include trailing commas after the last item, single quotes instead of double quotes around keys/strings, or unescaped control characters. Our validator highlights the exact location to fix.
Yes. Files Craft runs 100% in-browser JavaScript. Your data never leaves your computer, making it completely safe for sensitive API payloads.
Formatting (beautifying) adds line breaks and indentation to make JSON easy for humans to read. Minifying removes all extra spaces and line breaks to minimize bandwidth.
Yes, Files Craft JSON Formatter is 100% free with unlimited usage.