What does JSON formatting do?

JSON formatting adds proper indentation, line breaks, and spacing to make JSON data human-readable. It does not change the data — only the visual presentation.

How do I validate JSON?

Paste your JSON and click Format. If the JSON is invalid, the tool will show the exact error location and message so you can fix it.

Yes. Click Minify to remove all whitespace and compress JSON into a single line — reducing payload size for APIs and storage.

Is there a size limit?

No server-side limit. The tool runs in your browser and can handle JSON files up to several megabytes depending on your device.

Is my JSON data private?

Yes. All processing happens locally in your browser. Your JSON is never uploaded to any server.

JSON Formatter & Validator

Paste your JSON below to beautify, minify, or validate it instantly. Errors are shown with details so you can fix them quickly.

Input

Output

How to Use the JSON Formatter

Paste your raw or minified JSON into the input box on the left. Click "Beautify" to add proper indentation, "Minify" to compress it, or "Validate" to check for syntax errors. The formatted result appears on the right — click "Copy Output" to use it anywhere.

What is JSON?

JSON (JavaScript Object Notation) is a lightweight data format used to exchange data between servers and web applications. It's human-readable and supported by virtually every programming language. JSON uses key-value pairs, arrays, strings, numbers, booleans, and null values.

When to Use This Tool

Debugging API responses — paste a minified API response to see its structure clearly.

Validating config files — check package.json, tsconfig.json, or any config for syntax errors before deploying.

Minifying for production — compress JSON payloads to reduce bandwidth and improve API performance.

Learning JSON structure — use the Sample button to see a properly formatted example with nested objects and arrays.

Common JSON Mistakes

Trailing commas — JSON does not allow a comma after the last item in an object or array. This is valid in JavaScript but invalid in JSON.

Single quotes — JSON requires double quotes for keys and string values. Single quotes are not valid.

Unquoted keys — every key in JSON must be wrapped in double quotes, unlike JavaScript objects.

Comments — JSON does not support comments. Use JSONC or JSON5 if you need comments in config files.

Frequently Asked Questions

What is a JSON formatter?

A JSON formatter takes raw or minified JSON data and adds proper indentation and line breaks to make it human-readable. It helps developers quickly understand the structure of API responses, config files, and data objects.

What does JSON validation do?

JSON validation checks if your data follows correct JSON syntax — matching braces, proper quoting of keys, valid data types, and no trailing commas. If there's an error, the tool shows exactly where the problem is.

What is the difference between beautify and minify?

Beautify adds indentation and line breaks to make JSON readable. Minify removes all whitespace to make the JSON as compact as possible — useful for reducing payload size in APIs and storage.

Is my JSON data stored or sent anywhere?

No. All formatting and validation happens entirely in your browser using JavaScript. Your data never leaves your device.

Can I change the indentation size?

Yes. You can toggle between 2 spaces and 4 spaces indentation using the buttons above the output area.

What JSON errors can this tool detect?

The tool detects all syntax errors including: missing or extra commas, unquoted keys, single quotes instead of double quotes, trailing commas, mismatched brackets/braces, and invalid values.

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