jsonfmt

JSON Beautifier

Instantly format, indent, and beautify messy JSON data. Make unreadable JSON clean and structured — with syntax highlighting, configurable indentation, and optional key sorting. Free, fast, and private.

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What is a JSON Beautifier?

A JSON Beautifier is a tool that takes raw, minified, or poorly formatted JSON and transforms it into clean, human-readable output. It adds proper indentation, line breaks, and spacing so you can inspect nested data structures without squinting at a single unreadable line.

Whether you're debugging an API response, reviewing a config file, or cleaning up exported data — a JSON beautifier makes the process effortless. Our tool works entirely in your browser; your data never leaves your device.

Why Use a JSON Beautifier?

  • •Debug faster — Readable JSON makes it easy to spot missing keys, wrong values, and nesting errors in seconds.
  • •Share cleanly — Beautified JSON is much easier to paste into bug reports, documentation, or code reviews.
  • •Validate structure — Beautifying is a fast way to check if your JSON is valid before processing it further.
  • •No uploads, no tracking — All formatting happens locally in your browser. Your JSON never touches any server.

Features

Configurable Indentation

Choose 2-space or 4-space indentation to match your project's style guide or personal preference.

Sort Keys Option

Alphabetically sort object keys for consistent, diff-friendly output — handy for configuration files.

Syntax Highlighting

Color-coded output distinguishes strings, numbers, booleans, nulls, keys, and brackets at a glance.

Instant Validation

If your JSON is invalid, the tool highlights the error and tells you the exact line and character position.

How to Use

  1. 1
    Paste or type your JSON into the input editor on the main page.
  2. 2
    Choose your settings — pick indentation size (2 or 4 spaces) and toggle key sorting if desired.
  3. 3
    Click “Beautify” and copy the formatted result — or download it as a .json file.

Example

Before (minified)

{"name":"Alice","age":30,"active":true,"skills":["JS","TS","Go"]}

After (beautified, 2-space)

{
  "name": "Alice",
  "age": 30,
  "active": true,
  "skills": ["JS", "TS", "Go"]
}

Common JSON Issues

Trailing commas

JSON does not allow trailing commas. For example, [1, 2, 3,] is invalid. Remove any trailing commas before formatting.

Single quotes instead of double quotes

JSON requires double quotes for all keys and string values. Single-quoted strings like 'name' must be replaced with "name".

Unquoted keys

JavaScript object literals allow unquoted keys, but JSON does not. A key like { name: "Alice" } must be { "name": "Alice" }.

Ready to clean up your JSON?

Open JSON Beautifier