JSON Formatter, Minifier & Validator (Offline & Secure)
Format, validate, and beautify JSON directly in your browser. 100% private, client-side JSON formatting with syntax highlighting and validation.
How to use
- Paste your unformatted, minified, or messy JSON payload directly into the editor pane.
- The tool automatically detects syntax errors and instantly beautifies the JSON into a readable, strictly indented format.
- Expand or collapse nested objects using the gutter arrows.
- Click 'Copy' to copy the formatted JSON, or 'Download' to save it as a .json file locally.
Important Considerations
- Missing quotes around keys or trailing commas (which will trigger a syntax validation warning).
- Extremely large JSON payloads (over 5MB) which are processed smoothly entirely within your browser's memory without crashing.
Privacy Notice: This tool is strictly client-side. All processing runs in your local browser memory using JavaScript. No text, tokens, payloads, or logs are ever transmitted to any remote server or analytics engine. You can even use this tool completely offline.
Keyboard Shortcuts
- Ctrl/Cmd + KOpen Command Palette to switch tools instantly.