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JSON Formatter & Validator

No data is sent to any server. Everything runs locally in your browser.

Indent:
Input JSON
Formatted Output

What is a JSON Formatter?

A JSON formatter (also called a JSON beautifier or JSON pretty printer) takes raw, compact, or unformatted JSON and restructures it with proper indentation and line breaks so it becomes easy to read and understand. Whether you are debugging an API response, reviewing a config file, or inspecting data from a third-party service, a formatted JSON view saves significant time.

This tool also acts as a JSON validator — it instantly detects syntax errors and shows you exactly what went wrong, so you can fix issues without guessing.

Why Use This JSON Formatter?

  • 100% free — no account, no limits, no paywall.
  • Private — all processing runs in your browser. Your JSON never leaves your device.
  • Fast — instant results, even for large payloads.
  • Flexible input — paste text, upload a .json file, or load directly from a URL.
  • Multiple output modes — beautify with 2 or 4 space indent, or minify to a single line.
  • Sort keys — alphabetically reorder all object keys at every level for easy comparison.

Features

Beautify / Pretty Print

Adds indentation (2 or 4 spaces) and line breaks for readability.

Minify

Strips all whitespace to produce the smallest possible JSON output.

Validate

Checks JSON syntax and shows clear error messages with the exact issue.

Sort Keys

Sorts all object keys alphabetically at every nesting level.

Upload File

Load a local .json file directly from your device.

Load from URL

Fetch and format a JSON API response directly by URL.

Copy & Download

Copy output to clipboard or save it as a .json file.

Client-side Only

No data is ever sent to a server. Works offline after first load.

Frequently Asked Questions

What is JSON?

JSON (JavaScript Object Notation) is a lightweight, text-based data format used to exchange data between applications. It is human-readable and widely supported across all programming languages and platforms.

Is my data safe?

Yes. All formatting, validation, and processing happens entirely in your browser using JavaScript. Nothing is sent to any server. It is safe to paste sensitive or confidential JSON here.

What is the difference between Beautify and Minify?

Beautify adds indentation and line breaks to make JSON easy to read and debug. Minify removes all whitespace to produce the most compact output — useful for reducing payload size when sending JSON over a network.

What causes a JSON validation error?

The most common causes are: missing or extra commas, unquoted object keys, single quotes instead of double quotes, trailing commas after the last item, and mismatched braces {} or brackets [].

Can I load JSON from an API URL?

Yes. Paste the URL into the URL input field and click Load URL. The tool fetches the response and loads it into the editor. Note that the API must allow cross-origin requests (CORS) for this to work from a browser.

What does Sort Keys do?

Sort Keys reorders all object properties alphabetically at every nesting level. This makes it easy to compare two JSON objects side by side or to spot missing or extra fields.