About this tool
What it is, why it matters, and how to use it without common mistakes.
What is it?
A JSON formatter parses JavaScript Object Notation text, checks that it is syntactically valid, and pretty-prints it with consistent indentation so humans can read nested objects and arrays.
Why use it?
APIs, config files, and browser storage all speak JSON. A broken comma or quote wastes minutes; formatting and validating in the browser keeps sensitive payloads off third-party servers.
How it works
- Paste or type JSON into the editor.
- Run format to beautify, or minify to compress whitespace.
- Fix any syntax error the parser highlights before shipping the payload.
- Use related tools to diff, convert, or query the same document.
Examples
Pretty-print a nested object
{
"user": { "id": 42, "roles": ["admin", "editor"] },
"active": true
}Common invalid JSON
{'name': 'Ada'} // single quotes are not valid JSON — use double quotesBest practices
- Keep secrets local — prefer client-side tools for production tokens.
- Validate before storing JSON in databases or feature flags.
- Prefer UTF-8 and escape control characters correctly.
Common mistakes
- Trailing commas (allowed in JS, invalid in JSON).
- Unquoted keys or single-quoted strings.
- Treating undefined or NaN as JSON values.
FAQ
- Does formatting change the data?
- No. Whitespace between tokens is insignificant in JSON. Formatting only changes presentation.
- Is my data uploaded?
- code.live JSON tools run in your browser. Content stays on your device unless you explicitly use a feature that calls an API.