How to use the JSON formatter
JSON (JavaScript Object Notation) is the most common data format for API communication between a frontend and a backend. But JSON copied from an API response, a log file or a database is usually one long minified line that is nearly impossible to read by eye; sometimes it carries redundant spaces and line breaks that waste storage. This tool converts quickly between the two forms.
The four operations
- Beautify (format): expands minified JSON into indented levels so you can read it and troubleshoot. Choose 2 spaces, 4 spaces or a tab.
- Minify: removes every unnecessary space and line break to shrink the payload. Good for config files or passing as an API parameter.
- Escape to string: turns the whole JSON document into a backslash-escaped string, for nesting inside another JSON document or a code string.
- Unescape: restores an escaped JSON string back into a readable structure.
Pinpointing syntax errors
If the JSON you paste has a syntax problem (a trailing comma, single quotes, an unquoted key name are the usual suspects), the tool does not just say "invalid format" — it reports the exact line and column where the error occurs, so you can jump straight to it. That is more useful than what many online tools offer.
Sorting keys
With "sort by key" checked, the keys of every object in the output are reordered alphabetically. This is handy when comparing API responses, doing code review, or generating snapshot tests — two JSON documents with the same structure but different field order can be diffed directly once sorted.
Why everything runs locally
API data often contains user information, order numbers, internal field names, even secrets. Pasting that into someone else's server to parse it is a data-leak risk in itself. Here, parsing happens entirely inside your browser; technically your data never leaves your device. You can confirm this yourself in the Network panel of your browser's developer tools.
Frequently asked questions
How large a JSON file can it handle?
It depends on your machine's memory and your browser's performance. A few megabytes usually renders instantly. For very large files (tens of megabytes and up) a command-line tool is a better choice — browsers are slow at rendering that much text.
Why does my JSON report an error when it looks fine?
The three most common causes: a trailing comma after the last element, which the JSON standard does not allow; single quotes instead of double quotes, since JSON only accepts double quotes; and unquoted key names, which are legal in a JavaScript object literal but not in JSON. The tool reports the exact line and column.
Does sorting change the order of arrays?
No. Only object keys are sorted; array elements keep their original order. That matters, because array order often carries business meaning.
Do you store what I paste?
No. The content is gone the moment you refresh the page — nothing is stored and nothing is uploaded.