JSON Formatter
Pretty-print JSON with 2 or 4-space indentation. All processing runs in your browser — your data never leaves your device.
Tip: Press Ctrl+Enter to format.
What is a JSON Formatter?
A JSON formatter (also called a JSON beautifier or pretty-printer) takes compact or minified JSON and adds consistent indentation and line breaks, making it much easier to read and debug.
When to use it
- Inspecting API responses — paste a compressed response body and immediately see its structure.
- Debugging configuration files — spot missing commas, mismatched brackets, or incorrect nesting at a glance.
- Code reviews — share well-formatted JSON with teammates for clearer diffs.
Privacy
This tool uses the browser's built-in JSON.parse and JSON.stringify APIs. No data is transmitted to any server.
Frequently Asked Questions
Is my JSON payload sent to a server when formatting?
No. All parsing and string formatting runs strictly client-side using your browser's native JavaScript JSON engine. API payloads, database rows, and credentials never leave your device.
What size JSON payload can this tool format?
Because processing executes in your local browser memory rather than a remote server with payload limits, the tool can easily handle files up to tens of megabytes without network timeouts.
What indentation options are supported?
You can choose 2-space (the de-facto standard in JavaScript, Node.js, and web APIs) or 4-space (popular in Python, C++, and enterprise systems) indentation.
How do I fix invalid JSON syntax?
Common causes include single quotes instead of double quotes, trailing commas after array or object elements, or unquoted keys. Our tool highlights parse exceptions immediately so you can fix them.