New in Toolbox 1.1
Format and validate JSON on your Mac
Paste an API response or drop a .json file and JSON Formatter pretty-prints it with 2 spaces, 4 spaces or tabs, or minifies it to a single line. If the JSON isn't valid, it says what's wrong and points to the exact line and column. Keys stay in their original order unless you sort them, and numbers like 1.10 or 12345678901234567890 are kept exactly as written.
How to use JSON Formatter
Open JSON Formatter and paste JSON, or drop or open a .json file.
Choose Pretty or Minify, pick an indent and turn on Sort Keys if you want keys in alphabetical order.
If there's a mistake, read the message and click Show to select it in the input.
Click Copy, or Save to write a .json file.
Questions about JSON Formatter
How do I format JSON on a Mac without a website?
Paste it into JSON Formatter in Toolbox. The formatted result appears as you type, ready to copy or save, and nothing is sent to a server, which matters for API responses that contain tokens or customer data.
How do I find the error in invalid JSON?
JSON Formatter explains the problem in plain words and gives its line and column. Click Show to jump to the spot in the input.
Does it change key order or numbers?
No. Keys keep the order they were written in unless you turn on Sort Keys, duplicate keys are kept, and numbers keep their exact digits instead of being rounded.
Is it free, and does it upload my JSON?
Toolbox is a paid app, and one purchase includes every tool, with no subscription or account. JSON Formatter works offline on your Mac, so your data never leaves it.
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