About the JSON Formatter
JSON (JavaScript Object Notation) is the most common format for APIs, config files, and data exchange — but raw JSON is often delivered minified on a single line, which is almost impossible to read or debug. A JSON formatter (also called a JSON beautifier or pretty-printer) re-indents that data into a clean, hierarchical structure so you can scan it at a glance.
This formatter runs entirely in your browser, so your data is never uploaded to a server. Paste your JSON, and it instantly validates the syntax, pretty-prints it with your chosen indentation, and reports the exact line and column of any error. You can also minify JSON for production, sort keys alphabetically, and explore large payloads in a collapsible tree view.
Features
- Beautify minified JSON with 2-space, 4-space, or tab indentation
- Minify JSON to a single line to reduce payload size
- Validate syntax with precise line and column error locations
- Sort object keys alphabetically for consistent diffs
- Collapsible tree view for navigating deeply nested data
- Copy, download, or drag-and-drop a .json file — all client-side
How to use
- Paste your JSON into the input box, or drop a .json file onto it.
- Click Format JSON (or press ⌘/Ctrl + Enter) to beautify it.
- Pick an indent style, or toggle Minify for a compact one-liner.
- Switch to the Tree view to expand and collapse nested objects.
- Copy or download the result when you're done.
Frequently asked questions
Is my JSON data safe?
Yes. All formatting and validation happens locally in your browser using JavaScript — your data is never sent to or stored on any server.
What does 'minify' do?
Minifying removes all unnecessary whitespace and line breaks, producing the smallest valid JSON. This is useful for reducing the size of API responses or config files in production.
Why does it say my JSON is invalid?
Common causes are trailing commas, single quotes instead of double quotes, unquoted keys, or missing brackets. The tool shows the exact line and column so you can fix it quickly.