Does this send my JSON anywhere?

No — parsing, formatting, and validation all happen locally in your browser using standard JavaScript. Nothing you paste is transmitted or stored.

How accurate is the error location?

It's derived directly from the JavaScript engine's own parser error, converted into a line and column number — the same information the engine itself uses internally, not a separate guess.

What counts as "minified" vs "formatted"?

Minified removes all unnecessary whitespace to produce the smallest possible file size; formatted adds 2-space indentation and line breaks so it's readable. Both represent the exact same data.

Is there a size limit?

There's no hard-coded limit, but very large JSON files (several megabytes) may render the interactive tree slowly, since every node is a live, expandable element.

JSON Tree Formatter & Syntax Validator

Developer

Turn messy or broken JSON into a clean, color-coded tree.

Your JSON

Paste minified, messy, or broken JSON here.

Valid

Formatted tree

Click any row to expand or collapse it.

16 keys2 levels deep137 characters minified

id:"usr_8842"

name:"Jordan Lee"

active:true

"admin"

"editor"

city:"Austin"

zip:"78701"

lastLogin:null

About this tool

Paste minified, messy, or broken JSON and instantly get a validity check with the exact line and column of any syntax error, plus a collapsible, color-coded interactive tree view you can explore, and one-click copy for both formatted and minified output.

How to use JSON Tree Formatter & Syntax Validator

1
Paste your JSON into the input box — minified, pretty-printed, or broken all work.
2
If it's invalid, read the exact line and column of the syntax error.
3
If it's valid, explore the interactive tree — click any row to expand or collapse it.
4
Copy the formatted or minified version with one click.

Frequently asked questions

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