JSON Formatter
Paste messy JSON and turn it into clean, readable output.
Formatted JSON will appear here.
What is JSON Formatter?
JSON Formatter lets you instantly pretty-print, validate, and minify JSON right in your browser — no install, no login. Paste a raw API response, a config file, or a minified payload and the tool fixes indentation, highlights syntax errors inline, and shows you exactly where the problem is.
It also works in reverse: minify formatted JSON into a single compact line for embedding in code or API requests. The formatter handles nested objects, arrays, and escaped strings accurately, making it equally useful for debugging small snippets or large production payloads.
Common Use Cases
- Debugging and inspecting API responses
- Formatting config files and environment data
- Validating JSON before using in application code
- Minifying JSON for production payload size
- Finding exact line of a syntax error in malformed JSON
How to Use JSON Formatter
- Paste your JSON into the editor.
- Click Format to pretty-print with proper indentation.
- Fix any highlighted syntax errors shown inline, then copy the clean output.
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FAQ
Is my JSON sent to a server?
No. Everything runs in your browser. Your data never leaves your device.
Can it validate JSON syntax?
Yes. If your JSON has a syntax error, the formatter shows the error message and highlights the problem so you can find and fix it before copying the output.
What does the Format JSON button do?
It parses your JSON and re-renders it with consistent 2-space indentation, making nested structures easy to read.
What is the maximum JSON size it can handle?
It handles most real-world JSON files comfortably. Very large payloads (several MB) may feel slow depending on your device, since all processing happens in the browser.
Can I format JSON copied from an API response?
Yes. Paste the raw response body directly — the formatter handles minified, partially formatted, or deeply nested JSON without any extra steps.
What is JSON minification and when is it useful?
Minification removes all whitespace and newlines, reducing JSON to a single compact line. This shrinks payload size for API responses and config files, improving load times in production environments.