JSON Formatter
Prettify compact or minified JSON with proper indentation for easy reading and debugging.
Compact JSON from an API response or log file is notoriously hard to read — everything on one line with no indentation. A JSON formatter (also called a JSON prettifier or beautifier) adds consistent indentation and line breaks to make the structure visible at a glance. This tool formats any valid JSON with 2 or 4 space indentation, making nested objects, arrays, and deep hierarchies easy to navigate and debug.
📋 How to Use This Calculator
Paste compact or minified JSON into the input box. Select your preferred indentation — 2 spaces is the JavaScript and JSON community standard, while 4 spaces is common in Python. Click "Format / Prettify JSON" to instantly display the formatted output. Use the Copy button to grab the result. If you paste JSON from an API tool like Postman or curl, it may already be partially formatted; this tool will normalize it to consistent indentation regardless.
💡 Key Facts & Information
JSON formatting uses JSON.stringify(parsedObject, null, indent) — the built-in JavaScript function that serializes objects with configurable indentation. The formatter first validates your JSON (it will report an error for invalid input), then re-serializes with your chosen indent level. This means the formatter also normalizes inconsistencies in the input: it removes excess spaces, fixes mixed indentation, and produces a deterministic output. Many code editors (VS Code, IntelliJ) have built-in JSON formatters; this tool is useful when working outside an editor or for quick one-off formatting tasks.