JSON Formatter

A JSON formatter (also called a JSON beautifier or pretty-printer) takes minified or unformatted JSON and adds consistent indentation, line breaks, and spacing to make it human-readable. It's an essential tool for debugging API responses, reading config files, and reviewing data payloads.

Paste your JSON into the left panel, choose your preferred indentation style (2 spaces, 4 spaces, or tabs), and the output appears automatically on the right. You can also press Ctrl+Enter (or ⌘+Enter on Mac) to trigger formatting manually.

Both produce valid, semantically identical JSON. 2-space indentation is compact and preferred in JavaScript projects and many REST APIs. 4-space indentation follows Python's PEP 8 style and makes deeply nested structures slightly easier to read. Tabs are less common in JSON but useful when your editor is tab-configured.

Yes — entirely. All formatting is done by JavaScript running in your own browser tab. Your data is never transmitted to any server, never stored, and never logged. You can even disconnect from the internet and the tool continues to work.

If you see an error, your JSON has a syntax problem. Common causes: trailing commas ({'{"key": "val","}'}), single-quoted strings, unquoted keys, or missing closing brackets. The error message shows the exact line and column where the parser failed.