Inspecting a one - line API response
A one - line response makes it hard to find specific keys in nested objects. Formatting exposes the structure so you can quickly locate the fields you need.
JSON Formatter
Format, beautify, minify, and validate JSON instantly. Catch syntax errors with line numbers. Runs in your browser.
APIs return minified JSON, log files contain deeply nested objects, and config files grow unreadable over time. A quick formatter and validator lets you spot structure issues, find missing commas, and understand data shapes without firing up a full IDE.
How to use
Paste JSON, format it, and then follow the indentation to inspect nested keys and values.
- Paste raw JSON into the input area.
- Click Format to pretty - print or Minify to compact the JSON.
- Check the validation indicator for syntax errors and line numbers.
- Copy the formatted result to your clipboard.
Why this tool is useful
JSON is often shared as a single long line in logs, API responses, and webhook payloads. When JSON is compacted, it is hard to inspect nested structures or spot missing commas and braces. Even a small syntax issue can invalidate the entire payload.
Formatting JSON into an indented, readable structure makes debugging faster and reduces the risk of editing mistakes.
What this tool helps with
Pretty - printed JSON is easier to scan, review, and share. It helps you locate the exact part of a response or request that matters, and it makes it clearer when a field is missing or unexpectedly shaped.
When you need to edit or validate JSON, formatting reduces the chance of breaking structure because you can see brackets and object boundaries clearly.
Examples
Spotting syntax issues before sending a payload
A missing comma or brace can invalidate a request body. Formatting helps you visually verify structure and narrow down where an error might be.
Recommended for
Recommended if you: - debug API responses, webhooks, or logs that contain JSON - need to share JSON snippets with teammates for review - edit JSON configuration or test payloads - want quick validation and readability improvements
Privacy and processing
All processing happens in your browser. Your JSON data is never sent to our servers.
Frequently Asked Questions
What does this tool do?
It formats (pretty - prints) JSON with proper indentation, minifies JSON by removing whitespace, and validates JSON syntax with error messages and line numbers.
Is my JSON uploaded to a server?
No. All formatting, minifying, and validation happen entirely in your browser. Nothing is sent to any server.
Can it fix broken JSON?
No. The tool reports syntax errors with line numbers so you can fix them yourself, but it does not auto - correct invalid JSON.
What indent sizes are supported?
You can choose between 2 - space and 4 - space indentation.
Is there a size limit?
There is no hard limit, but very large JSON files may slow down your browser since processing happens client - side.
Does it preserve key order?
Yes. JSON.parse and JSON.stringify in modern browsers preserve insertion order of object keys.
Why do I see an error with a line number?
The JSON has a syntax error near that line. Common causes include missing commas, unclosed brackets, trailing commas, or unquoted keys.
Does this work offline?
Yes. Once the page has loaded, formatting and validation run without any network requests.
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