JSON Formatter & Minifier
Validate, beautify, and minify JSON data instantly in your browser.
JSON formatter online validates and beautifies raw JSON in your browser. Paste any JSON string and switch between text mode with syntax highlighting, an interactive tree view, and a table view. Beautify adds proper indentation. Minify strips all whitespace for production use. Sort keys alphabetically, search within large documents, and download the result as a .json file. No data leaves your device.
Frequently Asked Questions
- How do I format JSON online?
- Paste your JSON into the editor and click Beautify. The formatter parses the JSON and re-outputs it with 2-space indentation and proper line breaks. If the JSON is invalid, a red error message appears below the editor showing the exact parse failure.
- What is the difference between JSON format and JSON minify?
- Formatting (beautify) adds indentation and newlines to make JSON human-readable. Minifying removes all whitespace to reduce file size. A 10 KB formatted JSON file often shrinks to 3-4 KB after minification. Use minified JSON in production APIs and configuration files where humans do not need to read it.
- How do I validate JSON online?
- The editor validates JSON automatically as you type. A green "Valid JSON" badge appears when the structure is correct. A red "Invalid JSON" badge with an error message shows when something is wrong. Common errors are trailing commas, unquoted keys, and single quotes instead of double quotes.
- What is tree view in a JSON editor?
- Tree view displays JSON as an expandable node hierarchy. Objects and arrays show as collapsible folders. Each key-value pair appears on its own row. You can click to expand or collapse any branch. Navigating deeply nested documents becomes much faster. Scrolling through raw text to find a key is no longer necessary.
- How do I sort JSON keys alphabetically?
- Click the Sort keys button in the toolbar. The formatter recursively sorts all object keys at every depth level. Array order is preserved. Two objects with identical data but different key order become easy to compare after sorting.
- Is my JSON data safe when using this tool?
- All processing runs in your browser using JavaScript. No JSON is sent to any server. You can disconnect from the internet and the formatter will continue to work. JSON often contains API keys, passwords, or sensitive configuration data. Keeping all processing local protects that data.
What is JSON Formatter & Minifier?
JSON formatter online is a browser-based tool that validates, beautifies, and minifies JSON data. JSON stands for JavaScript Object Notation. JSON is the standard data format for APIs, configuration files, and web applications. Raw JSON from an API response is often a single unbroken line of text. The formatter parses it and re-outputs it with indentation, making it readable.
The editor uses CodeMirror with full syntax highlighting. Strings appear in green, numbers in amber, booleans in purple, and null values in grey. The gutter shows line numbers. Code folding lets you collapse any object or array to hide its contents temporarily.
How does it work?
Paste JSON into the editor. The formatter parses it using the browser's native JSON.parse. Beautify re-serialises using JSON.stringify with 2 or 4 space indentation. Minify re-serialises with no whitespace. Sort keys runs a recursive sort over all object keys before serialising.
The tree view converts the parsed object into an expandable node tree. Each node shows its key, a separator, and its value. Arrays show index numbers. Objects show key names. Boolean values have a toggle checkbox. You can edit values directly in tree view by clicking on them.
When should you use JSON Formatter?
Use it when debugging API responses. Copy the raw response body and paste it in to see the structure clearly. Use it before committing configuration files to check for syntax errors. Use Sort keys before comparing two JSON files in a diff tool so key order does not create false differences.
Minify before embedding JSON in JavaScript source code or HTML data attributes. A minified JSON string reduces page weight and avoids line-break issues in string literals. Download the formatted file to replace an unreadable config file on disk.
Tips to get the best results
- Switch to tree view for deeply nested JSON. Collapsing branches you are not working on reduces visual noise significantly.
- Use Sort keys before running a diff on two versions of the same config file. Sorting normalises key order so differences do not appear as changes.
- If validation fails, look at the error message carefully. Trailing commas are the most common culprit. A trailing comma after the last item is valid JavaScript but invalid JSON.
- For JSON files over 1 MB, try the table view. Table view works best when the top level is an array of objects with identical keys.