How can I format JSON?
Paste JSON, choose indentation and click “Format”.
JSON Formatter
Format, validate and minify JSON for free – no sign-up, with file upload, clear error display and local processing in your browser. Your data is not stored.
Your JSON data is processed directly in your browser. It is neither transmitted nor stored.
Your JSON data is processed locally in your browser only and is not stored.
Drop a JSON file here or select one (.json, .txt)
Sorting changes the order of object keys. Arrays remain unchanged.
Output
Structure analysis
JSON path
$
Understanding and using the JSON formatter
What is JSON?
JSON (JavaScript Object Notation) is a text-based, language-independent data format used for APIs, configuration and data exchange.
What is a JSON formatter?
A JSON formatter makes compact JSON readable with indentation and line breaks – pretty print.
What is a JSON validator?
A validator checks whether text is syntactically valid JSON and shows errors clearly.
What does minifying JSON mean?
Minifying removes unnecessary whitespace and line breaks without changing the data structure.
Which values does JSON support?
JSON supports objects, arrays, strings, numbers, booleans and null.
Why are single quotes invalid?
JSON requires double quotes for keys and string values. Single quotes are not allowed.
Are comments allowed in JSON?
No. The JSON standard does not support comments like // or /* */.
Why are trailing commas invalid?
There must be no comma after the last element in an object or array. Example: {"a":1,} is invalid.
What is the difference between JSON and JavaScript?
JSON is stricter than JavaScript object literals. Unquoted keys, functions or undefined are not allowed in JSON.
Is JSON data stored?
No. Processing happens entirely locally in your browser.
Related development tools
Frequently asked questions about the JSON formatter
How can I check if JSON is valid?
Use “Validate” or automatic validation while typing.
What is the difference between formatting and minifying?
Formatting makes JSON readable. Minifying removes whitespace for compact output.
Why is my JSON invalid?
Common causes are single quotes, trailing commas, missing brackets or comments.
Are single quotes allowed?
No. JSON requires double quotes.
Are comments allowed?
No. Comments are not part of the JSON standard.
Are trailing commas allowed?
No. There must be no comma after the last element.
Must JSON start with an object?
No. Strings, numbers, booleans, null or arrays are also valid JSON.
Can an array be valid JSON?
Yes. An array on its own is fully valid JSON.
Is a single number valid JSON?
Yes. Example: 42 is valid JSON.
Is my JSON data stored?
No. Everything happens locally in your browser.
Can I upload a JSON file?
Yes. .json and .txt files can be loaded locally.
Can I download formatted JSON?
Yes. Output can be downloaded as a .json file.
Can I sort object keys?
Yes. Enable “Sort object keys alphabetically”.
What does nesting depth mean?
It describes how deeply objects and arrays are nested inside each other.
Can the tool handle large JSON files?
Yes, up to 10 MB. Larger files are rejected.
What is the difference between JSON and JSON5?
JSON5 allows comments, single quotes and trailing commas. This tool supports standard JSON only.
Can the tool repair invalid JSON?
No. It provides hints but does not auto-repair.
Are special characters and umlauts supported?
Yes. Unicode in strings is handled correctly.
Is processing secure?
Yes. JSON is only parsed and displayed as text – never executed.