JSON Formatter
Format and validate JSON with proper indentation.
This JSON Formatter parses and pretty-prints JSON directly in your browser, with 2-space, 4-space, or tab indentation. It validates as it formats, pointing to the exact line and column where invalid JSON breaks. View results as formatted code, plain text, or an expandable tree, then copy or download the output — nothing is ever uploaded to a server.
How to use
- 1Paste JSON into the input, or upload a .json file — nothing leaves your browser.
- 2Click Format to validate and pretty-print it.
- 3Switch between Code, Text, and Tree views, then copy or download the result.
Frequently asked questions
What is a JSON formatter?
A JSON formatter takes minified or messily-indented JSON — often a single unreadable line — and re-indents it consistently so the structure of objects and arrays is easy to read and scan.
When would I need to format JSON?
Common cases: pasting an API response that came back as one long line, debugging a config file, or cleaning up JSON before sharing it with a teammate or including it in documentation.
Can it fix invalid JSON?
It will point out exactly where the syntax breaks — with line and column when possible — so you can fix it, but it won't guess your intent.
Is my JSON sent to a server?
No. Formatting happens entirely in your browser — your data never leaves your device.