JSON Pretty Print

What pretty printing does

A pretty printer parses your JSON and re-emits it with rules: a newline after every opening brace, one level of indentation per nesting depth, a single space after each colon, and a newline between items. The output is deterministic — the same input always produces the same layout — which is what makes it useful for reading, diffing and pasting into documentation.

Crucially, pretty printing never alters the data. It is a presentation transform. Run the result back through a minifier and you recover the original compact form exactly, because only optional whitespace differs between the two.

Pretty printing in code vs. online

Most languages can pretty print JSON natively. In JavaScript it is JSON.stringify(value, null, 2); in Python it is json.dumps(obj, indent=2); on the command line it is jq . or python -m json.tool. Those are perfect inside a script, but when you just have a string on your clipboard, opening an editor and writing code is overkill. An online pretty printer gives you the same canonical output with a paste and a click, and it lets you flip the indent size or sort keys without editing any code.

// JavaScript
JSON.stringify(data, null, 2)

# Python
json.dumps(data, indent=2)

# Shell
echo "$json" | jq .

Indent options

• 2 spaces — the most common choice on the web and in JavaScript tooling.
• 3 spaces — occasionally used to keep deep nesting from drifting too far right.
• 4 spaces — favoured in Python, Java and many enterprise style guides.
• Tab — lets each developer pick a display width in their own editor.

Whichever you choose, the printer applies it uniformly across every level, so the result is consistent from the first brace to the last.

Local, fast and private

This pretty printer runs entirely in your browser. There is no upload step, so the JSON you paste — including production responses and anything containing credentials — stays on your machine. It also means there is no latency: the formatted output appears the moment you stop typing, even for large documents. If you lose your connection mid-task the tool keeps working, because the printing logic is JavaScript that already loaded with the page.